Homeowner's Frequently Asked Questions

Everything You Ever Wanted To Know...

...And Some Things You Didn't

 

If You Have Some General Questions About Roofing, Attic Ventilation, Or Mold Issues, Please Read Through Our Homeowner's FAQs Guide.

Mold, Moisture, and Your Home

Mold Basics

  • The key to mold control is moisture control. 
     
  • If mold is a problem in your home, you should clean up the mold promptly and fix the water problem. 
     
  • It is important to dry water-damaged areas and items within 24-48 hours to prevent mold growth.

Why is mold growing in my home?

Molds are part of the natural environment.  Outdoors, molds play a part in nature by breaking down dead organic matter such as fallen leaves and dead trees, but indoors, mold growth should be avoided.  Molds reproduce by means of tiny spores; the spores are invisible to the naked eye and float through outdoor and indoor air.  Mold may begin growing indoors when mold spores land on surfaces that are wet.  There are many types of mold, and none of them will grow without water or moisture.

mold growing outdoors on firewood[At Left - Mold growing outdoors on firewood.  Molds come in many colors; both white and black molds are shown here.

Can mold cause health problems?

Molds are usually not a problem indoors, unless mold spores land on a wet or damp spot and begin growing.  Molds have the potential to cause health problems.  Molds produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins).  Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals.  Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis).  Allergic reactions to mold are common.  They can be immediate or delayed.  Molds can also cause asthma attacks in people with asthma who are allergic to mold.  In addition, mold exposure can irritate the eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people.  Symptoms other than the allergic and irritant types are not commonly reported as a result of inhaling mold.  Research on mold and health effects is ongoing.  This brochure provides a brief overview; it does not describe all potential health effects related to mold exposure.  For more detailed information consult a health professional.  You may also wish to consult your state or local health department.

magnified mold spores

How do I get rid of mold?

It is impossible to get rid of all mold and mold spores indoors; some mold spores will be found floating through the air and in house dust.  The mold spores will not grow if moisture is not present.  Indoor mold growth can and should be prevented or controlled by controlling moisture indoors.  If there is mold growth in your home, you must clean up the mold and fix the water problem.  If you clean up the mold, but don't fix the water problem, then, most likely, the mold problem will come back.

 

Who Should Do the Cleanup?

leaky window[Click on the image for a larger 300dpi JPG file]

Who should do the cleanup?

Who should do the cleanup depends on a number of factors.  One consideration is the size of the mold problem.  If the moldy area is less than about 10 square feet (less than roughly a 3 ft. by 3 ft. patch), in most cases, you can handle the job yourself, following the guidelines below.  However:

  • If there has been a lot of water damage, and/or mold growth covers more than 10 square feet, consult the U.S. Environmental Protection Agency (EPA) guide: Mold Remediation in Schools and Commercial Buildings.  Although focused on schools and commercial buildings, this document is applicable to other building types.  It is available free by calling the EPA Indoor Air Quality Information Clearinghouse at (800) 438-4318, or here at epa.gov/mold/mold_remediation.html.
     
  • If you choose to hire a contractor (or other professional service provider) to do the cleanup, make sure the contractor has experience cleaning up mold.  Check references and ask the contractor to follow the recommendations in EPA's Mold Remediation in Schools and Commercial Buildings, the guidelines of the American Conference of Governmental Industrial Hygenists (ACGIH), or other guidelines from professional or government organizations.
     
  • If you suspect that the heating/ventilation/air conditioning (HVAC) system may be contaminated with mold (it is part of an identified moisture problem, for instance, or there is mold near the intake to the system), consult EPA's guide Should You Have the Air Ducts in Your Home Cleaned? before taking further action. Do not run the HVAC system if you know or suspect that it is contaminated with mold - it could spread mold throughout the building.  Visit epa.gov/iaq/pubs/airduct.html, or call (800) 438-4318 for a free copy. 
  • If the water and/or mold damage was caused by sewage or other contaminated water, then call in a professional who has experience cleaning and fixing buildings damaged by contaminated water.
     
  • If you have health concerns, consult a health professional before starting cleanup.

Mold Cleanup Guidelines

bathroom tips

Tips and techniques

The tips and techniques presented in this section will help you clean up your mold problem.  Professional cleaners or remediators may use methods not covered in this publication.  Please note that mold may cause staining and cosmetic damage.  It may not be possible to clean an item so that its original appearance is restored.  Click on the images below for a larger 300dpi JPG version.

mold growing on lawnchair

  • Fix plumbing leaks and other water problems as soon as possible.  Dry all items completely.
     
  • Scrub mold off hard surfaces with detergent and water, and dry completely.
     
  • Absorbent or porous materials, such as ceiling tiles and carpet, may have to be thrown away if they become moldy.  Mold can grow on or fill in the empty spaces and crevices of porous materials, so the mold may be difficult or impossible to remove completely.
     
  • Avoid exposing yourself or others to mold (see discussions: What to Wear When Cleaning Moldy Areasand Hidden Mold).
     
  • Do not paint or caulk moldy surfaces.  Clean up the mold and dry the surfaces before painting.  Paint applied over moldy surfaces is likely to peel.
     
  • If you are unsure about how to clean an item, or if the item is expensive or of sentimental value, you may wish to consult a specialist.  Specialists in furniture repair, restoration, painting, art restoration and conservation, carpet and rug cleaning, water damage, and fire or water restoration are commonly listed in phone books.  Be sure to ask for and check references.  Look for specialists who are affiliated with professional organizations.

mold growing on a piece of ceiling tile

 

What to Wear When Cleaning Moldy Areas

moldy suitcase

  • cleaning moldAvoid breathing in mold or mold spores.  In order to limit your exposure to airborne mold, you may want to wear an N-95 respirator, available at many hardware stores and from companies that advertise on the Internet. (They cost about $12 to $25.)  Some N-95 respirators resemble a paper dust mask with a nozzle on the front, others are made primarily of plastic or rubber and have removable cartridges that trap most of the mold spores from entering.  In order to be effective, the respirator or mask must fit properly, so carefully follow the instructions supplied with the respirator.  Please note that the Occupational Safety and Health Administration (OSHA) requires that respirators fit properly (fit testing) when used in an occupational setting; consult OSHA for more information (800-321-OSHA or osha.gov/ ).
     
  • Wear gloves. Long gloves that extend to the middle of the forearm are recommended.  When working with water and a mild detergent, ordinary household rubber gloves may be used.  If you are using a disinfectant, a biocide such as chlorine bleach, or a strong cleaning solution, you should select gloves made from natural rubber, neoprene, nitrile, polyurethane, or PVC (see Cleanup and Biocides).  Avoid touching mold or moldy items with your bare hands.
     
  • Wear goggles.  Goggles that do not have ventilation holes are recommended.  Avoid getting mold or mold spores in your eyes.

How Do I Know When the Remediation or Cleanup is Finished?

You must have completely fixed the water or moisture problem before the cleanup or remediation can be considered finished.  

  • You should have completed mold removal.  Visible mold and moldy odors should not be present.  Please note that mold may cause staining and cosmetic damage.
     
  • You should have revisited the site(s) shortly after cleanup and it should show no signs of water damage or mold growth.
     
  • People should have been able to occupy or re-occupy the area without health complaints or physical symptoms.
     
  • Ultimately, this is a judgment call; there is no easy answer. If you have concerns or questions call the EPA Indoor Air Quality Information Clearinghouse IAQ INFO at (800) 438-4318.

 

Moisture and Mold Prevention and Control Tips

moisture control is the key to mold control

  • Moisture control is the key to mold control, so when water leaks or spills occur indoors - ACT QUICKLY.  If wet or damp materials or areas are dried 24-48 hours after a leak or spill happens, in most cases mold will not grow.
     
  • Clean and repair roof gutters regularly.
     
  • Make sure the ground slopes away from the building foundation, so that water does not enter or collect around the foundation.
     
  • condensation on the inside of a windowpaneKeep air conditioning drip pans clean and the drain lines unobstructed and flowing properly.
  • Keep indoor humidity low.  If possible, keep indoor humidity below 60 percent (ideally between 30 and 50 percent) relative humidity.  Relative humidity can be measured with a moisture or humidity meter, a small, inexpensive ($10-$50) instrument available at many hardware stores. 
     
  • If you see condensation or moisture collecting on windows, walls or pipes ACT QUICKLY to dry the wet surface and reduce the moisture/water source.  Condensation can be a sign of high humidity.

Actions that will help to reduce humidity:

  • Vent appliances that produce moisture, such as clothes dryers, stoves, and kerosene heaters to the outside where possible.  (Combustion appliances such as stoves and kerosene heaters produce water vapor and will increase the humidity unless vented to the outside.)
     
  • Use air conditioners and/or de-humidifiers when needed.
     
  • Run the bathroom fan or open the window when showering.  Use exhaust fans or open windows whenever cooking, running the dishwasher or dishwashing, etc.

Actions that will help prevent condensation:

  • Reduce the humidity (see above).
     
  • Increase ventilation or air movement by opening doors and/or windows, when practical.  Use fans as needed.
     
  • Cover cold surfaces, such as cold water pipes, with insulation.
     
  • Increase air temperature.

mold growing on a wooden headboard

condensation on a drainpipe

Testing or Sampling for Mold

Is sampling for mold needed?  In most cases, if visible mold growth is present, sampling is unnecessary.  Since no EPA or other federal limits have been set for mold or mold spores, sampling cannot be used to check a building's compliance with federal mold standards.  Surface sampling may be useful to determine if an area has been adequately cleaned or remediated.  Sampling for mold should be conducted by professionals who have specific experience in designing  mold sampling protocols, sampling methods, and interpreting results.  Sample analysis should follow analytical methods recommended by the American Industrial Hygiene Association (AIHA), the American Conference of Governmental Industrial Hygienists (ACGIH), or other professional organizations.

 

Hidden Mold

mold growing on the back side of wallpaperSuspicion of hidden mold

You may suspect hidden mold if a building smells moldy, but you cannot see the source, or if you know there has been water damage and residents are reporting health problems. Mold may be hidden in places such as the back side of dry wall, wallpaper, or paneling, the top side of ceiling tiles, the underside of carpets and pads, etc. Other possible locations of hidden mold include areas inside walls around pipes (with leaking or condensing pipes), the surface of walls behind furniture (where condensation forms), inside ductwork, and in roof materials above ceiling tiles (due to roof leaks or insufficient insulation).

Investigating hidden mold problems

Investigating hidden mold problems may be difficult and will require caution when the investigation involves disturbing potential sites of mold growth. For example, removal of wallpaper can lead to a massive release of spores if there is mold growing on the underside of the paper. If you believe that you may have a hidden mold problem, consider hiring an experienced professional.

Cleanup and Biocides

Biocides are substances that can destroy living organisms. The use of a chemical or biocide that kills organisms such as mold (chlorine bleach, for example) is not recommended as a routine practice during mold cleanup. There may be instances, however, when professional judgment may indicate its use (for example, when immune-compromised individuals are present). In most cases, it is not possible or desirable to sterilize an area; a background level of mold spores will remain - these spores will not grow if the moisture problem has been resolved. If you choose to use disinfectants or biocides, always ventilate the area and exhaust the air to the outdoors. Never mix chlorine bleach solution with other cleaning solutions or detergents that contain ammonia because toxic fumes could be produced.  Click on the image below for a larger 300dpi JPG file.

Please note: Dead mold may still cause allergic reactions in some people, so it is not enough to simply kill the mold, it must also be removed.

water stain on a basement wall

 

Additional Resources

mold growing on fallen leavesFor more information on mold related issues including mold cleanup and moisture control/condensation/humidity issues, you can call the EPA Indoor Air Quality Information Clearinghouse IAQ INFO at (800) 438-4318, or:

How to order publications

IAQ INFO
P.O. Box 37133, Washington, DC 20013-7133
1-800-438-4318/703-356-4020
(fax) 703-356-5386
iaqinfo@aol.com

U.S. Environmental Protection Agency
National Center for Environmental Publications (NSCEP)
P.O. Box 42419
Cincinnati, OH 42419
1-800-490-9198/(513) 489-8695 (fax)

Fighting Mold - The Homeowner's Guide

Understanding mold

      • Mold can be harmful or helpful—depending on where it grows.
      • Mold needs moisture to grow.
      • Mold does not grow on dry materials.
      • Mold growing inside a home can affect the occupants.
      • Occupants can learn to recognize mold.

What are molds?

Molds are microscopic fungi, a group of organisms which also includes mushrooms and yeasts. Fungi are highly adapted to grow and reproduce rapidly, producing spores and mycelia in the process.

You encounter mold every day. Foods spoil because of mold. Leaves decay and pieces of wood lying on the ground rot due to mold. That fuzzy black growth on wet window sills is mold. Paper or fabrics stored in a damp place get a musty smell that is due to the action of molds.

Molds can be useful to people. The drug penicillin is obtained from a specific type of mold. Some foods and beverages are made by the actions of molds. The good kinds of molds are selected and grown in a controlled fashion.

Molds are undesirable when they grow where we don’t want them, such as in homes. Over 270 species of mold have been identified as living in Canadian homes. Molds that grow inside may be different from the ones found outdoors.

What makes molds grow?

Molds will grow if we provide them with moisture and nutrients. If we keep things dry, molds do not grow. High moisture levels can be the result of water coming in from the outside, through the floor, walls or roof; or from plumbing leaks; or moisture produced by the people living in the home, through daily activities like bathing, washing clothes or cooking. Water enters the building when there is a weakness or failure in the structure. Moisture accumulates within the home when there is not enough ventilation to expel that moisture.

Different kinds of molds grow on different materials. Certain kinds of molds like an extremely wet environment. Other kinds of molds may be growing even if no water can be seen. Dampness inside the material can be enough to allow them to grow.

Why are molds a concern?

Damage to materials is one concern. Materials get stained or discolored, and over time they are ruined. Moldy paper and cardboard disintegrate over time. Fabrics are damaged. Continued mold growth can be indicative of moisture conditions favorable for growth of fungi that cause wood rot and structural damage.

When molds are growing inside the home, there may be health concerns. Molds release chemicals and spores.

Health experts indicate that, depending on the type of mold present in a home, the amount and degree of exposure, and the health condition of the occupant, the health effects of mold can range from being insignificant to causing allergic reactions and illness.

Pregnant women, infants, the elderly and those with health problems, such as respiratory disease or a weakened immune system, are more at risk when exposed to mold. Consult your family physician if you believe there is someone who may be at risk.

How can you tell if it is mold?

Discoloration

Discoloration is a sign of mold. However, all discoloration is not due to mold. Carpeting near baseboards, for example, can be stained by outdoor pollution entering the home. Stains or soot may also be caused by the smoke from burning candles or cigarettes.

Mold may be any colour: black, white, red, orange, yellow, blue or violet. Dab a drop of household bleach onto a suspected spot. If the stain loses its colour or disappears, it may be mold. If there is no change, it probably isn’t mold.

Smell/Odour

Sometimes molds are hidden and cannot be seen. A musty or earthy smell often indicates the presence of molds. But a smell may not be present for all molds. Even when you don’t notice a smell, wet spots, dampness or evidence of a water leak are indications of moisture problems and mold may follow.

Is there a mold problem?

Molds are always found in the air outside and in all buildings. They come into the home in many ways —through open windows or doors, on clothing, pets, food or furniture. The problem starts when mold grows inside the home.

Some mold growing, for example on the window sill but not elsewhere, is not a cause of concern.You can clean the mold yourself. The presence of mold is a sign that there is too much moisture in your home—a situation which must be corrected.

Inspect the home to find the extent of the mold.

How much mold is growing?

One way is to estimate the area of the mold.

Mold is considered to cover a “small area” if the patch is no larger than a square meter. There should be no more than three patches, each patch smaller than a square meter. Clean up small areas yourself using a detergent solution, household rubber gloves and a dust mask for protection. Refer to How to Clean up small mold problems for the procedure.

Small moldy areas in homes may become larger over time, if ignored, so it’s important to clean up and remove even small patches of mold.

The mold area is considered “moderate” if there are more than three patches, each patch smaller than a square meter, or there is one or more isolated patches larger than a square meter but smaller than 3 square metres (size of a 4 x 8 foot sheet of plywood).

Assessment by a professional is recommended. You can clean up moderate amounts of mold but you must follow the proper procedures and use the proper protective equipment. Refer to How to Clean up moderate mold problemsfor the procedure.

A mold area is considered “extensive” if a single patch of mold is larger in area than a sheet of plywood. Being exposed to this much mold is not a good idea. Do not attempt to clean up large areas of mold yourself.You need professional help to determine why the mold is there in the first place and how to clean it up.

      • Estimate how much mold is growing.
      • You can clean up a “small area” of mold yourself.
      • For larger mold areas or recurrent mold problems, seek professional help.

When should you seek professional help?

You may need professional help when:

      • there is a lot of mold;
      • the home is very damp and moist;
      • mold comes back after repeated cleaning; and
      • a family member suffers from asthma or respiratory problems or other health problems that appear to be aggravated inside the home.

How do you get professional help?

Contact your local CMHC office for a list of individuals who have completed the CMHC Residential Indoor Air Quality Investigator program. A trained IAQ investigator, who operates a private business and sells his/her services, examines the indoor air quality of your home and documents your concerns. He/she identifies the problems, finds their sources and suggests solutions in a written report. Recommendations are provided to you in an action plan that consists of various options to improve the indoor air quality in your home.

How to clean up small mold problems

      • “Small areas” of mold can be cleaned with a detergent solution.
      • Wear a mask, safety goggles and rubber gloves.
      • Seek professional help if there is a lot of mold or if mold comes back after cleaning.
      • Clean “moderate areas” of mold, but wear proper protective equipment and follow precautions.
      • Seek professional help if there is a lot of mold or if mold comes back after cleaning.

“Small area” clean-up

You can clean up “small areas” of mold (fewer than three patches, each smaller than a square meter) yourself. The minimum protective wear needed are:

      • safety glasses or goggles;
      • a disposable dust mask (3M 8210 or equivalent); and
      • household rubber gloves.

Infants and other family members with asthma, allergies or other health problems should not be in the work area or adjacent room during the cleaning.

Steps to follow in cleaning up small mold areas

Washable surfaces:

      • scrub with an unscented detergent solution; then
      • sponge with a clean, wet rag and dry quickly.

Using an unscented detergent will make it easier for you to detect residual moldy odours.

Moldy drywall:

      • clean the surface with a damp rag using baking soda or a bit of detergent. Do not allow the drywall to get too wet.

Mold that comes back after cleaning is usually an indication that a source of moisture has not been removed. Seek professional help from a trained IAQ investigator.

How to clean up moderate mold problems

      • Clean “moderate areas”of mold, but wear proper protective equipment and follow precautions.
      • Seek professional help if there is a lot of mold or if mold comes back after cleaning.

If you follow the proper procedures and use the proper protective equipment, you can clean up “moderate areas”of mold. “Moderate” means more than 3 patches of mold, each smaller than one square meter, or one or more isolated patches larger than one square meter but smaller than 3 square metres (size of a 4 x 8 foot sheet of plywood).

a) Safety precautions

      • Wear a disposable dust mask (for example, 3M 8210 or equivalent), glasses or safety goggles and household rubber gloves.
      • Isolate the area to be cleaned with plastic sheeting, taped to walls and ceiling.
      • Infants and other family members suffering from asthma, allergies or other health problems should not be in the work area or adjacent room during the cleaning.

A small clean up should take minutes (not hours) to finish. When the clean up takes hours to a day to finish, it is suggested that you upgrade to a better filter, such as a half-face respirator with charcoal cartridges. An exhaust fan installed in a window in the room being cleaned would prevent contamination of other areas of the house as well as provide ventilation.

b) General cleaning

Vacuum surfaces with a vacuum cleaner which has a High Efficiency Particulate Air (HEPA) filter or is externally exhausted. Scrub or brush the moldy area with a mild unscented detergent solution. Rinse by sponging with a clean, wet rag. Repeat. Dry quickly.

HEPA vacuum the surfaces that were cleaned as well as surrounding areas.

c) Cleaning wood surfaces

Vacuum mold from wood surfaces using a HEPA or externally exhausted vacuum. Skip the vacuuming step if the wood is wet. Clean with a detergent solution then sponge with a clean, wet rag. Extract the moisture using a dry/wet vac and/or clean, dry rags. Accelerate the drying with fans and open windows. If the relative humidity outside is high, use a dehumidifier. The wood should not be allowed to remain wet for more than a day.

If cleaning with detergent and water does not remove the mold, try sanding the surface with a vacuum sander (simultaneous vacuuming and sanding). Do not attempt to sand without vacuuming. This method will not work if the mold has penetrated to the core of the wood. Severely moldy wood should be replaced.

d) Cleaning concrete surfaces

Vacuum the concrete surfaces to be cleaned with a HEPA or externally exhausted vacuum cleaner. Clean up surfaces with detergent and water. If the surfaces are still visibly moldy, use TSP (trisodium phosphate). Dissolve one cup of TSP in two gallons of warm water. Stir for two minutes. Note: TSP must not be allowed to come in contact with skin or eyes. Saturate the moldy concrete surface with the TSP solution using a sponge or rag. Keep the surface wetted for at least 15 minutes. Rinse the concrete surface twice with clean water. Dry thoroughly, as quickly as possible.

e) Moldy drywall

The paper facings of gypsum wallboard (drywall) grow mold when they get wet or repeatedly wet and don’t dry quickly. Cleaning with water containing detergent not only adds moisture to the paper but also can eventually damage the facing. If the mold is located only on top of the painted surface, remove it by general cleaning (See above). If the mold is underneath the paint, the moldy patch and other moldy material behind it are best cut out and the surrounding areas also cleaned. This should be done by a mold clean-up contractor. New materials may become moldy if the moisture entry has not been stopped. If this is the case, replacement of the materials should be deferred until the source of the moisture is corrected. The affected areas should be temporarily covered with plastic sheeting and sealed at the edges.

Any areas that show new patches of mold should be cleaned promptly.

Dealing with an ongoing problem

      • Water entering the home from the outside requires repair to the building envelope.
      • Owners can reduce exposure to mold in their homes.

Repair to the building envelope is required if moisture is entering the home from the outside. At the same time, steps should be taken inside the home to reduce the occupants’ exposure to mold.

      1. Discard moldy or damaged materials.Wear a dust mask and gloves. Furnishings, such as mattresses, carpets, or sofas that got wet or have been stored in damp conditions should be discarded. Discard items that are no longer needed. Use this opportunity to reduce the amount of furnishings—means less materials that absorb moisture and grow mold. Clothes and other items that have been cleaned should be stored in sealed plastic bags to prevent re-contamination.
      2. Proper vacuuming reduces the amount of mold spores. All surfaces in the home (floors, walls, ceilings, shelves) and non-washable furnishings (such as sofas, chairs, etc.) must be vacuumed thoroughly.
      3. Keep moisture generated within the home to a minimum by conscientiously following the prevention steps below.
      4. Pull carpets and furnishings away from walls that get wet. Carpets and underpads that are moldy should be cut out and discarded.
      5. Take steps to dry up areas that get wet. Monitor the relative humidity of the air. Use a portable dehumidifier, if necessary. Ensure that the condensate drain pan of the dehumidifier is emptied regularly.
      6. If the mold is limited to one area, isolate the area if possible. Cover the affected surfaces with plastic sheeting secured at the edges with duct tape. Note that this is only a temporary measure to minimize your exposure.
      7. Healthy individuals can regularly clean “small” and “moderate” areas of mold, thus preventing these from getting out of hand, by following the safety precautions and cleaning guidelines.
      8. Consider seeking professional help from trained IAQ investigators to identify appropriate remediation steps inside the home. Removing large amounts of mold will require the services of mold clean-up contractors.

Preventing mold

      • Keep the home dry.
      • Find and fix water leaks.
      • Discard clutter and excess stored materials.
      • Clean and maintain the home regularly.
      • Encourage lifestyle practices that reduce moisture.

Basic steps to prevent and reduce mold growth

Mold needs moisture to grow. Controlling the moisture and keeping the home dry prevents the growth of mold.

      • Check your home for signs of moisture and molds.
      • Find out if water is coming in from the outside and if substantial moisture is produced inside the home.
      • Fix any water leaks promptly.
      • Think of the different ways moisture is produced inside the home (for example, cooking, bathing, plant jungle). Remove the moisture as it is produced by using exhaust fans. In the absence of fans, open windows for a short time, but note that the wind can push the moisture to other parts of the home.
      • Measure how much moisture is in the air.To find the relative humidity in your home, you’ll need a hygrometer. You can buy one at a hardware store or electronics store.A hygrometer costs from $5 to $20. Relative humidity in the home should be under 45 per cent in the winter (or lower to avoid condensation on windows). If necessary, use a dehumidifier to lower the relative humidity.
      • Reduce the amount of stored materials, especially items that are no longer used. Molds grow on fabrics, paper, wood and practically anything that collects dust and holds moisture.

Mold-proofing your home, room by room

Basement or crawl space

      • Reduce the amount of clothes, paper and furnishings stored in the basement. Discard badly damaged materials. Eliminate clutter to improve air circulation. Only washable items should be stored.
      • Dehumidify the basement during the warm months.
      • Avoid carpets on slab-on-grade or below grade floors.
      • Periodically clean the drain in your basement floor. Use half a cup of bleach, let it stand for a few minutes, then flush with plenty of water. Keep the drain trap filled with water.
      • Avoid standing water. Keep sump pits covered (you can use plywood wrapped with plastic).
      • Regularly clean and replace furnace filters. Use a pleated one-inch filter, not a coarse filter.
      • If you have a heat recovery ventilator (HRV), clean the filter inside the HRV often.
      • If you notice molds or signs of dampness, such as water on your windows or wet spots elsewhere, do not humidify. Disconnect furnace humidifiers that are no longer used.
      • If you have electric baseboards, vacuum the units, or have a professional clean them for you.

Laundry areas

      • Check that your clothes dryer exhausts to the outside.
      • Remove lint every time you use the dryer.
      • Don’t hang-dry laundry indoors.
      • Dry your laundry tub and washing machine after you use them.

Bathrooms

      • Check the bathroom fan to make sure it exhausts to the outside.
      • Turn the bathroom fan on when you shower. Keep it running for a few minutes after you finish your shower.
      • Take short showers.
      • Keep surfaces that get wet, such as the walls around the bathtub and shower, clean and dry.
      • If there is a carpet in your bathroom, remove it.
      • Check for water leaks.
      • Keep drains in good shape by removing debris from them.

To clean a drain:

      • Pour a handful of baking soda into it.
      • Add a cup of vinegar.
      • Put the plug in the drain.
      • Let the vinegar and baking soda work for about 20 minutes.
      • Run fresh water into the drain.

If the drain is still clogged, use a small plumbing snake.

Kitchen

      • If the fan over your stove exhausts outside, use it when you cook.
      • Minimize open boiling.
      • Keep your drains in good shape. Follow the steps in the Bathrooms section, above.
      • There’s a drip pan at the back of the refrigerator. Pull the refrigerator out to clean the drip pan. At the same time, vacuum dust from the coils at the back of the refrigerator.
      • Check under the kitchen sink to make sure there are no leaks.
      • Take out the garbage daily to prevent odours and spoiling.

Closets and bedrooms

      • Get rid of clothes and other stored items that you don’t use. Keeping your closets and bedrooms tidy makes it easier for air to circulate —and harder for mold to grow.

Other parts of the home

      • A dehumidifier helps to reduce moisture in the home during the warmer months. Close the windows when the dehumidifier is running.
      • When family and friends come into the home, have them take off their shoes.
      • Vacuum often. If you are buying a vacuum cleaner, try to get one with a HEPA filter. (See below).
      • Clean hard floors with a damp mop.
      • Do not bring in furniture, clothing, books etc. that have been stored in a moldy place into your home.
      • Cut down the number of potted plants in the house—soil is a good place for mold.

Exterior

      • Regularly check the condition of the roof and exterior finish for any places where water might enter.
      • Make sure that eavestroughs and downspouts are connected and working properly and that they are free of debris.
      • Install downspout extensions to lead water away from the building.
      • Deal promptly with any problems that you find.

Frequently asked questions about mold

Should I have my house air tested for mold?

This is the question most frequently asked by homeowners who think their home may have a mold problem. Testing is generally not recommended for homeowners.Testing of moldy materials or an air sample identifies the types of molds that may be present but does not identify the cause/source of moisture.The type of mold does not change the procedures for cleaning up areas of mold less than 3 square meters. You have to clean up the mold and correct the problem irrespective of the type of mold. The cost of testing may be better spent hiring a professional investigator or fixing the problem.

Testing of a moldy material involves sending a swab, imprint on a Scotch tape or piece of the material to a competent laboratory. Air sampling requires specialized equipment. An air sample typically captures mold spores in a period of minutes. Since replicate samples must be taken due to variations in the airborne molds over time (even hours) and compared with outdoor samples, air testing is both expensive and time-consuming. Interpretation of test results may not be very useful, since there are no advocated "safe levels" of indoor molds and the results will not tell the health risks from the molds.

The air feels dry—can I humidify?

Before you add moisture to the air, measure the relative humidity. Air that feels dry may not be really dry. It may be moldy. High relative humidity (over 45 per cent) promotes the growth of molds and dust mites.The moisture in the air may condense on colder exterior walls where molds start to grow.

If your physician has advised you to use a humidifier in your child’s bedroom at night, monitor the relative humidity.Turn the humidifier on and off as necessary. In the morning, take steps to make sure the room gets dry. Clean and empty the humidifier after each use.

What advantages do HEPA vacuums provide?

Ordinary vacuums capture large particles only—small mold spores pass through the vacuum into the air. HEPA vacuums have special filters that capture small particles. A central vacuum cleaner which is exhausted to the outside also removes mold spores. A regular portable vacuum is useful only if its exhaust goes outside the home. Vacuuming removes settled dust that contains an accumulation of mold spores over time. Reducing the settled dust reduces molds.

Vacuuming with any vacuum cleaner (ordinary, central or HEPA) stirs dust and mold during the process. Wear a dust mask so you will not be breathing more mold.

Is vacuuming with a HEPA or externally exhausted vacuum cleaner recommended for serious mold problems only?

Vacuum regularly with a HEPA or externally exhausted vacuum cleaner to prevent the ongoing accumulation of dust and molds. The need for HEPA or external exhaust vacuuming increases with the severity of the mold problem.

If a furnishing has been wet at some time in the past or has been exposed to dampness over a prolonged period of time, vacuuming with HEPA or externally exhausted vacuum is unlikely to remove the mold growing beneath the surface. It is better to discard the item.

Where do you find a HEPA vacuum cleaner?

Vacuum cleaner dealers carry HEPA vacuums. Consider purchasing one as an upgrade to what you may be using. A HEPA vacuum is a good investment in the long term whether you have mold or not. A generic canister HEPA vacuum cleaner costs approximately $300. Brand name products of the same type may cost more.You may inquire if the dealer has a HEPA vacuum cleaner to rent. Contractors who clean up or renovate houses for mold should also have this equipment.

Does painting over a moldy surface take care of the mold?

Painting over mold only masks the problem. Paint does not kill the mold nor stop it from growing. Surfaces that are washable should be cleaned with a detergent solution, following the procedure suggested above, then allowed to dry. If you are going to paint, remove mold first.

Does cleaning stop the mold growth?

Mold will reappear until its source of moisture is removed. High moisture levels that are not corrected can make the molds grow back quickly. Cleaning is only a temporary but essential measure.

You can help by making a conscious effort to keep the home dry. Obviously, water must be prevented from entering the home. But you can help by controlling moisture that you produce.

How does one clean clothes that are moldy?

Non-washable clothing can be dry cleaned.

Wash clothes with a detergent solution to which a cup of bleach is added. Make sure the detergent you use does not contain ammonia. Repeat as necessary until the moldy odour is gone.

Clothes and other items that have been cleaned should be stored in sealed plastic bags to prevent re-contamination

General Ventilation Troubleshooting

Use these troubleshooting questions to help you answer general questions about ventilation or more specific questions about ridge vents, intake vents, power vents and whole-house fans.

General

How much attic ventilation do I need for my attic?
Air Vent recommends 1 square foot of attic ventilation for every 150 square feet of attic floor space divided evenly between intake vents at the overhang or undereave and exhaust vents at or near the peak of the roof. Here's what the formula looks like for a 1200 square foot attic space: 1200 divided by 150 = 8 square feet of attic ventilation. Then divide that number by 2 to provide half the ventilation for intake and half for exhaust. Thus, 8 divided by 2 = 4 square feet of attic ventilation for intake and 4 square feet of attic ventilation for exhaust.

The final step is to figure out how many vents would be needed to provide 4 square feet of attic ventilation. To do this let's start by converting the number to square inches by multiplying by 144. Thus, 4 x 144 = 576 square inches of attic ventilation for intake and 576 for exhaust. Air Vent ridge vents provide 18 square inches of Net Free Area per linear foot. To determine how many feet of ridge vent would be needed the formula looks like this: 576 divided by 18 = 32 feet of ridge vent. A typical 8" x 16" undereave vent provides 56 square inches of Net Free Area per vent. To determine how many undereave vents would be needed, the formula looks like this: 576 divided by 56 = 10.2 (which can be rounded up to 11).

I have attic ventilation but why doesn't my attic seem to be any cooler? 
With any attic ventilation system, the attic could be about 20 degrees hotter than it is outside. Attic ventilation is meant to protect the roof sheathing, insulation and shingles from temperature and moisture extremes. However, many variables will affect the temperature that the attic can reach. For example, the color of the shingles will have a large impact on the temperature. Black shingles will cause the attic to be much hotter than if white shingles were used. Other factors are the geographical location, intensity of the sun, orientation of the primary roof plane, and amount of total ventilation NFA.

What products do you have that will work on a flat roof?
All Air Vent products are designed for sloped roofs with a minimum 3/12 pitch. Unfortunately, Air Vent products are not designed for flat roofs.

What size nails should I use?
Taking in to account the size of the felt paper, shingles and roofing deck, the nails should always penetrate the roof deck. If the nails do not penetrate the roof deck, the vent can start to pull up the roofing nails.

Do I need to oil the motor on my fan?
No, it is not necessary to oil the motor. The bearings are pre-lubricated for life.

Ridge Vents

What size slot do I cut for your ridge vent?
For ridgepole construction, cut a 3/4" slot on each side of the ridgepole. For truss construction, cut a 1.5" slot at the peak of the roof.

What is the purpose of the filter in the ridge vent?
Air Vent's internal weather filter is designed to be a secondary layer of defense against weather, dust and insect infiltration in the attic.

Do I have to close off my gable vents when I use a ridge vent?
Yes, the gable vents (a type of exhaust vent) should be closed off whenever a ridge vent (which is also a type of exhaust vent) is installed because vents installed in the overhang or undereave area should supply the intake air needed by the ridge vents. Air should flow in through the overhang evenly along the roofline and exhaust out the peak. Any vents in place between the ridge vents and the overhang or undereave area may interrupt or short-circuit that flow of air along the roofline. The gable vents will end up becoming intake for the ridge vent — an undesirable situation that could lead to weather infiltration through the gable vents and also could prevent the attic from being properly ventilated.

How does the external baffle work?
As wind hits the external baffle it is forced over the ridge vent creating a low air pressure above the vent openings on the ridge vent. This low pressure above the vent openings allows air to be pulled from the attic through the exhaust vent — enhancing the vent's performance. There's a special name for this phenomenon. It's called the Bernoulli Effect and it's the same principal that gives lift to an airplane.

Can I install a power fan if I have a ridge vent already on my roof?
Mixing a power vent with a ridge vent can short-circuit the attic ventilation system just as a gable vent can as discussed above. This happens because air follows the path of least resistance. When the power vent turns on, it can pull air from the ridge vent, which could lead to weather infiltration and unbalanced airflow along the underside of the roof deck. When the power vent turns off, it acts like a roof louver — an opening on the roof without a motor. In this scenario, the ridge vent pulls its intake air from the power fan leading to possible weather infiltration and less than optimal ventilation along the underside of the roof deck.

Basically, mixing two different types of exhaust vents on the same roof is not recommended because it can lead to short-circuiting of the attic ventilation system.

Can I use your ridge vent on the hips?
No. In fact, Air Vent does not recommend using ridge vents on the hips because water may flow down into the ridge vent.

Intake Vents

How important is intake ventilation for ridge vent?
Intake ventilation is very important for all types of exhaust vents, including ridge vents. Each attic should have an equal amount of intake ventilation at the overhang or undereave as it has exhaust at or near the peak of the roof. This is known as a balanced ventilation system.

If there isn't enough intake ventilation in the overhang or undereave, for example, the ridge vent can pull air from one side of itself right out the other side. Picture a wave going into the vent and right out. The problems with ridge vents pulling air in one side and out the other is that it will only be ventilating the very peak of the roof instead of the entire underside of the roof deck. Furthermore, it could bring into the attic precipitation from outside.

I don't have any overhang. Can I use roof louvers or roof pots near the bottom of the roofline?
A roof louver (they are also called roof pots or can vents) placed low on the roof can lead to weather infiltration because the roof louver is not designed to be an intake vent. As water flows down the roofline air is coming into the roof louver. This can result in water entering the vent. In situations where there isn't an overhang, Air Vent recommends using a vented drip edge type vent that will provide more protection from weather infiltration and allow an even flow of air along the underside of the roof deck.

I have a knee wall. What should I do?
In a knee wall situation the goal is to get the intake airflow past the wall. There are two ways to do this.

  1. If the roof deck is being replaced, install insulation baffles in every rafter from the overhang or undereave level to the peak of the roof. This will allow an even flow of air along the roof deck that will flow past the knee wall.
  2. Slide wood slats up the underside of the roof deck (for short spans only) and then flip them on edge to force down the insulation. Pull down the fascia to allow access to the underside of the roof deck from outside the house. Someone can feed the wood slats from outside while someone in the knee wall area guides the slats toward the ridge.

Power Vents

My power attic ventilator has burned out completely. What do I need to check to make sure this doesn't happen again?
Check the intake ventilation. Make sure that the attic insulation has not covered the intake vents preventing air from feeding the power vent. It might be necessary to either insert insulation baffles or to pull the attic insulation back to ensure the intake vents are not blocked.

Also check to make sure that the plywood the intake vents are installed in have actually been cut or opened to allow for air to flow into the vent.

Finally, make sure that the power vent has enough intake vents. To determine how many intake vents the power vent requires, take the CFM (cubic feet of air moved per minute) of the vent and divide it by 300. This will determine the square feet of intake ventilation needed. Take that number and convert it to square inches by multiplying by 144. For example, 1500 CFM divided by 300 = 5 square feet of intake ventilation needed. Converting to square inches looks like this: 5 x 144 = 720 square inches of intake ventilation needed for the power vent.

If you don't know the CFM of the power vent or the net free area of the intake vents, check with the manufacturer.

My power attic ventilator runs all the time. Is there anything I can do?
Set the humidistat higher. The numbers on the humidistat control run from 1 to 9, which is 10% to 90%. If it's set too low, the power vent will run all the time. Set it around 8.

Can I use Air Vent power attic ventilators around chemicals?
The motor on Air Vent power vents is not closed, which means chemicals could affect the motor. Air Vent recommends not using power vents around chemicals.

Can I use a gable-mount power attic ventilator to vent a workshop, restaurant, dry cleaners, etc?
Air Vent gable-mount power attic ventilators are meant for attic spaces in residential houses. The reason they will not usually work in an open space is the power vents need an outside flow of air. The power vents pull air from outside through intake vents in the overhang or undereave. If the power vents don't have that outside flow of air, the motor will burn out.

Why do I need a humidistat with my power attic ventilator?
The thermostat control on a power attic ventilator monitors the attic solely for temperature or heat buildup. Thus, the power vent will only run in the hot summer months. During the winter, moisture can build up causing a reduction in the effectiveness of your insulation. The humidistat allows the power vent to run in the winter, which will keep the moisture from building up.

My turbines aren't spinning. Why?
Generally, if standing outside while the wind is blowing the turbines should be spinning. If the turbines spin by hand but not in the wind then the bearings are probably too tight. If it's an internally braced wind turbine, be sure that the upper bearing is straight and tightly fastened to the crown plate (top plate) of the turbine. If it's an externally braced wind turbine, make sure that there is about 1/8" of the shaft showing between the top of the upper bearing and the underside of the brace plate (plate that the 3 external braces rivet to at the top of the turbine). In both cases be sure that the retaining cap on the bottom of the lower bearing assembly is snapped securely in place and not crooked.

Whole-House Fans

Can I mount the whole-house fan vertically?
Air Vent whole-house fan cannot be mounted vertically. There are several reasons for this. First, the shutter will not open or close in a vertical position. Second, the fan blade will eventually crack over time. Third, if mounted on a vertical wall facing the outside the fan will pull the air from outside into the attic rather than attic air being vented to the outside. Unfortunately, the fan blades and motors are not reversible. If the motor is reversed, it will burn out. If the fan blades are reversed they will crack. The warranty on Air Vent whole-house fans requires installation in a horizontal position.

Why is the shutter for my whole-house fan a different size from the whole-house fan?
The rough opening that is cut for the shutter is a different size so the whole-house fan can be pushed through the opening from inside the hallway rather than try to get it through a smaller attic opening.

Why do I have to cut a joist for the belt-drive fan?
The louvers on the shutters all open up towards the fan. If the joist is not cut, the louvers will hit the joist and get bent.

The shutter on my whole-house fan rattles and is very noisy. What can I do?
Open more windows. Sometimes there is not enough air moving towards the shutters and the louvers cannot open all the way. Another thing to try is putting felt strips or rubber stripping on each louver to give the louvers a little weight and catch the vibration from the whole-house fan. Check to make sure there is enough clearance above the fan. A minimum of 30" of clearance above the whole-house fan blades is needed. Without this clearance, the air will be forced back through the shutter. Also check to make sure there is enough exhaust ventilation, which includes both intake vents in the overhang or undereave as well as exhaust vents high on the roof at or near the ridge. Without enough exhaust ventilation, air will also be forced back through the shutter. It might be necessary to add a 2" x 4" to the housing of the fan to give more clearance between the fan and the shutter.

Can I use a rheostat with your fan?
No, if a rheostat is used on Air Vent fans, the motor will burn out.

My fan is vibrating a lot. Anything I can do?
Remove the fan blade and see if the motor still vibrates. If the vibration is gone, it means the fan blade is out of balance. If there is still a lot of vibration, a bearing could have been knocked loose.

Can my control on my fan be mounted upside down?
Yes, as long as the controller is in the flow of the fan, it can be mounted upside down.

My whole-house fan will only run on low. What is wrong with it?
Check to make sure there is enough exhaust ventilation, including intake vents in the overhang or undereave as well as exhaust vents high on the roof at or near the ridge. Possibly there isn't enough exhaust ventilation for the whole-house fan to run at the higher setting.

Call the manufacturer to find out the net free area of all the vents in your attic (intake vents at the overhang and exhaust vents at or near the ridge). Most net free areas are less than half the size of the vent. For example, a 12" x 12" gable vent's unobstructed airflow is 56 square inches even though the opening measures 144 inches. Calculate the unobstructed airflow of all the vents in your attic, whether it is a ridge vent, gable vents or undereave vents. If they equal the minimum requirements for the whole-house fan, the fan should run on high.

General Attic Ventilation FAQ

How much attic ventilation do I need?

  • For non-powered attic vents (ridge vents, roof louvers, wind turbines, etc.) Building codes give minimum attic ventilation requirements. Most attics require more. In fact, research suggests you need 1 square foot of ventilation space, or net free area, for every 150 square feet of attic floor space. Net free area is the total unobstructed area through which air can enter or exhaust a non-powered vent.
  • For new home construction with a vapor retarder, the minimum is 1 square foot of ventilation or net free area for every 300 square feet of attic floor space. If your vents are split between ridge vents and intake vents, the minimum requirement is also 1 square foot of ventilation or net free area for every 300 square feet of attic floor space
  • For power attic vents Power Attic Ventilators are rated in CFM. This number represents the cubic feet of air moved per minute. The higher the CFM, the more powerful the ventilator. According to the Home Ventilating Institute, to determine the correct CFM rating needed, multiply attic square footage by 0.7. For example: 1500 square footage (attic) x 0.7 = 1050 CFM (look for a power ventilator rated 1050 CFM or higher. When using power vents, be sure to provide sufficient attic intake ventilation to match the exhaust capacity of the fan. To determine this, divide the CFM by 300 for the number of square feet of intake needed. Because most vents are rated in inches instead of feet, simply multiply the number of square feet by 144 to calculate the net free area of intake needed.
  • For whole-house fans. Whole-House Fans are also rated in CFM. To determine the right size for your house, calculate the interior square footage of living area (do not include garage, attic or basement) and multiply the total square footage by three. This will give you the CFM number to look for when choosing your whole-house fan.

How do I install a balanced ridge vent system?
A balanced system of intake and exhaust airflow through the attic is the best way to create effective, year-round ventilation. Thus, in addition to installing ridge vents, which act as exhaust vents, be sure your attic has intake vents in the soffit/eaves.

To ensure a balanced ventilation system, match the amount of net free area the ridge vent provides with as much, or more, intake area. To do so, measure the length of ridge vent you will be installing, then double that length for Air Vent continuous soffit vents because the net free area (NFA) of the soffit vent is 9" and the NFA of the ridge vent is 18".

How does the Air Vent external baffle work?
Air Vent ridge vents feature an advanced designed, external baffle that is one of the keys to the ridge vent's outstanding performance. The baffle deflects wind up and over the vent, creating an area of low pressure above the vent openings that causes lift. This is called the Bernoulli Effect. It's the same effect that causes airplane wings to lift. This low pressure works to pull air out of the attic. The baffle also deflects wind over the vent to help prevent wind-blown rain and snow from entering the attic.

What if a ridge vent doesn't have an external baffle?
With an unbaffled ridge vent, wind and other elements can blow directly in through the ridge vent. Air entering the vent can create pressure in the attic, which prevents air and moisture from being pulled out. Also, stronger winds can actually pass through one side of the vent and out the other, which also prevents air and moisture from escaping the attic. Tests show that externally baffled vents outperform unbaffled ridge vents.

What does Air Vent's internal weather filter do?
Air Vent's internal weather filter provides a more complete barrier from the elements. Wind-driven rain, snow, dust and insects are trapped by the filter. And because Air Vent ridge vents provide continuous airflow along the entire roof, the internal weather filter is cleaned by the flow of air coming out of the attic. Only Air Vent has an internal weather filter.

How can I prevent ice dams?
Ice dams are barriers to water runoff on the roof. They usually form at the roof edge, just above the gutter, in cold, snowy climates. They form when snow melting on warmer areas of the roof, usually near the ridge, runs down and refreezes at colder roof overhangs. Warm spots on the roof are caused by the heat that escapes from the living space into the attic. Once this cycle of melting and refreezing begins, a barrier is formed, trapping the snowmelt and allowing it to flow up and under shingles. As water begins to penetrate sheathing, insulation, wall cavities, and sheetrock or plaster:

  • paint can begin peeling on both inside and outside walls
  • roof coverings, fascia and gutters can be damaged
  • structural damage can result from the weight of the ice dam

Homeowners usually blame their gutters, since that's where the problem appears to be. But newer, wider, deeper gutters won't solve the problem. Nor will additional layers of insulation alone. What will solve it is adequate ventilation combined with proper levels of insulation.

What is a cold roof system and how does it help prevent ice dams?
The key to solving ice dams is to create a cold roof, with the temperature of the inside roof sheathing near that of the outside air temperature. To create such a condition, large volumes of outside air must enter at soffit intakes, sweep along ridge rafters, then exit at vents near the ridge. To prevent trapping warm air in the attic, an equal balance must be established between intake and exhaust air volumes.

Since such a ventilation system is bringing cold air into an attic, the insulation must minimize heat loss at the attic floor. As an added precaution, use waterproofing shingle underlayment. It provides a waterproof-barrier beneath roof shingles that pooled water from melting ice dams and driven rain cannot penetrate.

What is air exchange?
Air exchange is a system of air intake and exhaust that occurs with effective air circulation. When stale, overheated air in your home or attic is vented out and fresh air is pulled in to replace it, that's air exchange. In an attic, for example, cool air enters intake vents, which are located along the underside of the eaves. It's warmed, then rises out of the roof or gable attic vents to expel heat.

What are the benefits of installing a power vent with a thermostat/humidistat?
With combination thermostat/humidistat controls, power attic ventilators monitor heat and humidity levels in summer through winter for year-round attic protection from the damaging effects of moisture and heat buildup.

Moisture naturally generates in homes from washers, dryers, dishwashers and showers. The water vapor travels upward, passing through ceilings and insulation until it reaches cooler, dryer conditions in the attic. When the vapor hits cooler rafters, trusses and roof sheathing, it rapidly condenses into water droplets or frost. The trouble starts as water begins to drip into the attic or wick into the sheathing.

  • Water stains may form on ceilings just under the attic and the paint may peel
  • Up in the attic, the insulation may become damp and compressed
  • Mold and mildew can develop in the attic
  • Wood can rot
  • Deterioration of roof shingles accelerates

The advantage of the combination thermostat/humidistat is it provides double protection throughout the year.

What is the benefit of two-speed controls on power ventilators?
Adjustable, factory-set, two-speed controls can save homeowners energy and money by automatically switching from high to low speed depending on daily attic temperature fluctuations. On a typical summer day, the two-speed power attic ventilator runs on low during early morning and late afternoon, automatically adjusting to peak heat conditions midday by switching to high speed.

The HomeOwner's Guide To Reroofing

INTRODUCTION

So you need to reroof your home, but you're not quite sure where to start? Or maybe you have reroofed your home before, but you need to brush up on some of the latest products and procedures? Well, you've come to the right place.

Your decision to reroof your home may have been the result of seeing a neighbor reroof his or her home. Or maybe you've been experiencing some roofing problems which can no longer be ignored. Then again, maybe you've decided just to give your home a face lift and a new roof would really enhance the look. Whatever the reason, you don't want to make any costly mistakes!

To help you through the process, we've broken down the reroofing process into three specific areas: Getting Started, Selecting a Product, and Reroofing Procedures. Our brochure outlines each of these areas and lists the most commonly asked questions concerning each topic, with straightforward answers to help resolve some of your uncertainties.

Not surprisingly, there are a number of pitfalls to which homeowners can fall victim, including evaluating and hiring a contractor without a personal interview, judging estimates on low price only, selecting products without comparison shopping, and not understanding reroofing basics. We suggest using this brochure in combination with our "Choosing a Professional Roofer" brochure in order to get maximum benefit. You'll find that being prepared and knowing what to expect when reroofing work begins will help ensure your ultimate satisfaction with your new roof.

GETTING STARTED

When it comes to reroofing, there are a number of areas homeowners need to be aware of– from selecting a contractor to the actual start of work. We’ve outlined the six most commonly asked questions by homeowners with regard to getting started.

1. How do I find a professional roofing contractor?

Referrals are the best place to start. Ask a neighbor who recently had his roof replaced about his contractor and if he was happy with the work done.

The second best place to seek out a professional contractor is to go to your local building distributor or lumber yard dealer and ask them. We are not referring to the large home center or retail store chains, but rather professional roofing material distributors who work with reputable contractors on a regular basis.

The Yellow Pages is usually the third place homeowners can look. You should interview 2-3 different contractors, whether they are referrals or from the Yellow Pages.

Ask for 8-10 references, meaning job-site locations or names of homeowners, from each contractor interviewed.The following are additional points to consider in evaluating contractors:

  • Repeat business in nearby area;
  • Length of time in business;
  • Willingness and ability to handle complaints quickly and fairly;
  • Completeness and professionalism of estimate offered and presentation given. Make judgments based on the quality and number of jobsite photos shown (these should include names, phone numbers and completion dates), presentation of proper insurance, number of references offered, proposal provided, etc. Do not base professionalism on the sole criteria of having a legible business card.
  • Membership in professional associations; and, 
  • Knowledge and thoroughness of roofing procedures.

Do not consider any bids from contractors you have not met or interviewed. Check with your City Hall if you are unsure.

To help you find a professional contractor, we've designed a special brochure, "Choosing a Professional Roofer". You might have received a copy of our Roofer brochure with this pamphlet. If not, write to us at the address listed in the back for a free copy.

2. How many estimates should I get before selecting a roofing contractor? What is the best way to judge an estimate?

Although you may receive a reliable, fair estimate from the first contractor interviewed, you should usually obtain two additional estimates to help you determine which one is best. In judging the cost of a job, you should evaluate the following:

• The contractor–basing your evaluation on the likelihood that during the next three to five years, the period in which any imperfections in the roof system are most likely to occur, the contractor can be located, will stand behind his warranty, and will provide the service he promised; 
• The quality and completeness of the roof system recommended–making sure the complete roof system will include ventilation and waterproofing shingle underlayment (if appropriate to your region and your home’s structure); 
• The quality of the product choices offered–expect to pay a higher price for designer or architectural shingles (further explanation regarding product selection is provided in the next section); and, 
• The completeness of the contractor’s insurance package–protecting you from involvement in worker injuries, third person liabilities, and damages consequential to the work being performed.

MOST IMPORTANT: Never judge the value of various proposals from the lowest bid received. A low price can signal a lot of discrepancies and shortcomings in the reliability of the contractor.

3. How long is it reasonable to expect to wait after I select a contractor for work to begin?

Weather permitting–a common period from contract signing to job start is 2-6 weeks. This can vary a great deal depending on the time of year and the contractor’s backlog. Job start delays and postponements are a fact of life in a trade which is highly dependent on weather. However, the contractor also has a responsibility to you to be straightforward about his availability right from the start. He should also advise you on a timely basis about any changes in the schedule originally set.

4. What is the typical duration of a reroofing job?

The duration of the job varies widely depending on the size and complexity of the roof. A small, uncomplicated roof job can usually be finished in a day or two. A large, complex project can last a week or more. Once started, however, a job should not be interrupted for any reason other than weather.

If, on the other hand, a problem arises in the reroofing process, it might be necessary to halt the work to negotiate a change in the contract. You should always be advised of any changes which affect the contract agreement. A well-drafted, professional contract will anticipate unforeseen problems such as hidden deck rot, etc. These conditions can be incorporated in “not to exceed price” or “time and material” clauses.

5. How does extreme weather affect re-roofing projects?

Bad weather and extreme temperatures can interrupt or postpone roofing projects. Safety of the worker is the first consideration. This can be an issue in both hot and cold weather. Windy, wet and icy weather present dangers on a roof. Shingles are also affected by temperature extremes. Cold weather will delay activation of the sealant. This is not a reason to delay a project unless the shingle manufacturer prohibits installation at low temperatures for warranty purposes. Experienced installers who exercise care can usually avoid this problem.

6. Should I expect to pay a deposit when I sign an agreement?

Deposit requirements vary from contractor to contractor. While it is not considered unreasonable to pay a deposit you should never pay for the total job up-front. It is not recommended that the total deposit and progress payments equal more than 75% of the total job price (some state laws regulate this amount).

Deposits should not be held over more than two months without consideration for the cost of money. Long-term deposits can be placed in escrow or interest costs can be credited against the cost of the job as a term of the contract.

It is not recommended to give a deposit to a contractor whose track record cannot be verified by references from recent work.

NOTE: Before signing the contract or agreement, make sure the price covers all materials, gutters, ventilation, clean-up, completion date, etc.

SELECTING A PRODUCT

Selecting roofing shingles is no different than purchasing a major home appliance or even a new car: You should investigate your options carefully, comparison shop, and weigh the costs against features and benefits desired.

Just like choosing a car, the overriding factor in selecting a roofing shingle is knowing whether your primary goal is function only or function plus aesthetics. With a car, you know whether you want a sporty, knock-em-dead car or a practical sedan with room for several passengers. It’s the same with roofing shingles.

Sometimes a homeowner who is looking to reroof for functional reasons may see a standard three-tab roofing shingle on a neighbor’s home and decide to go with the same product choice–maybe even the same color. But if appearance is a major factor in your reroof decision, then take the time to really look around. You may want to visit a local distributor to obtain product literature and see the various designer shingle choices available. The following are the five most important questions you can ask when choosing a roofing shingle.

1. What’s the difference between an architectural or designer shingle and a standard shingle?

Since the early 1900’s, the three-tab or strip shingle was the standard composition shingle installed on single family residences. These products come with 20, 25, and 30 year warranty coverage. Color is about the only appearance differentiation in this class of shingle. In 1965, CertainTeed Corporation introduced the Hallmark Shangle™, the first architectural or designer shingle on the market. The standard laminated “dragon-tooth” design followed that. Other important innovations in architectural shingles include the Super Shangle and Super Shake styles. Today, the architectural shingle class is running away with the market. Warranties range up to 40 years and even life-time. Color is no longer the only choice to make. The many textures, forms, and designs of architectural shingles in the marketplace can result in a major aesthetic upgrade for your home.

Ask your contractor to show you a Good, Better, and Best selection of products. Shingles are not just for keeping out the rain, anymore.

2. What type of warranty should I look for? Aren’t they all the same?

Warranties usually range from 20 to 40 years. CertainTeed has a lifetime warranty. Yet, as an increasing number of contractors and homeowners tell us, the length of the warranty is not as meaningful to them as upfront coverage in the few years following application. This is the time when, according to contractors, problems caused by defects are most likely to occur. As a result you should:

• Look for manufacturers’ warranties that cover materials and labor in the first three to five years after application on any grade of roofing shingle. 
• Carefully review the manufacturer’s warranty stipulations about proration and transferability. Three Tab/Strip Standard Laminated Super Shangle 
• Proration is the reduction of the manufacturer’s contribution to the homeowner for repairing or replacing defective shingles during the warranty period. Select products carrying a warranty that does not prorate during the first three to five years after installation. Also, make sure the warranty prorates on the current market cost of the replacement shingles (as opposed to the original cost of the defective shingles).
• Examine the manufacturer’s stipulations on ventilation and warranty validation. Shingle roof system failure as the result of inadequate ventilation may cause the shingle warranty to become invalid. (See question regarding roof ventilation in “Reroofing Procedures” for further explanation.)
• Note the contractor’s guarantee of performance. Contractors’ guarantees are usually for one to five years on the average. Remember that the length of the contractor’s guarantee is less important than his ability or intent to stand behind his workmanship and to service a valid complaint in a reasonable time period. This intent must be determined from referrals and references and his general reputation in the local business community.

3. What does the U.L. fire resistance rating for a shingle mean?

The Underwriters Laboratories (U.L.) ratings signify that the shingles were manufactured to pass a certain set of standards to qualify as fire resistant.

Organic shingles carry a U.L. Class C fire resistance rating. Fiber glass shingles carry a U.L. Class A fire resistance rating. Either is appropriate for residential applications.

Some local building codes may have ordinances specifying a certain U.L. Class for your residential area. Your contractor or local building codes officer can tell you what the requirements are for your particular area.

REROOFING PROCEDURES

While we do recommend hiring a professional contractor to reroof your home, you should, nevertheless, familiarize yourself with certain aspects of the reroofing process. The fact is, there are various conditions about your roof that may limit your product choices or affect the cost of your roofing job. Consequently, you should learn about these certain circumstances if and when your contractor approaches you about them. Here’s a list of questions and answers that are relevant to the reroofing process.

1. Do I need to obtain a permit to install a new roof on my home?

Some local ordinances require permits be obtained prior to the start of roofing work in both new and some reroofing jobs, depending on the locale.

If a permit is required, discuss with your contractor who will obtain it and how it will be obtained. If your contractor agrees to obtain the permit, make sure your contract states this clearly.

Your roofing contractor should know if a permit is required in your area for reroofing jobs. You can also double-check with your local building codes officer to be sure.

2. What is roof slope? Does the slope of the roof limit the choice of shingle that can be used?

The slope of the roof is measured by the rise vs. the run, or the number of inches vertically by the number of feet horizontally. Some roof slopes can limit the choice of shingles that can be used.

For Instance:

• A roof slope below 2/12 (2 inches per one foot) cannot use shingles. 
• Roof slope between 2/12 and 4/12 require lowslope application techniques, including application of waterproofing underlayment as appropriate. 
• Roof slopes above 21/12 require steep-slope application techniques.

Your roofing contractor should consult the application instructions found on each shingle bundle wrapper or installation instructions supplied separately for further details.

3. Is it always necessary to tear off existing shingles before reroofing? If they are torn off, who is responsible for the disposal of the old shingles?

There are two options available for reroofing installations. One would be to tear off the old roof before applying the new one (tear off). The second would be to lay new shingles over the existing roof (lay over). While the second choice is the less expensive of the two options, it is not necessarily always the best choice.

There are advantages to tearing off the old roof before installing a new one. For example:

• If there are any defects in the roof deck, they will be revealed when the roof is torn off. These defects should be repaired before applying the new roof. 
• If condensation problems exist in the attic, they too will be revealed when the roof is torn off. Properly designed attic ventilation can then be installed in order to help eliminate such problems. 
• When the old roof is torn off, waterproofing shingle underlayment can be installed before applying the new roof. This will help protect against cyclical ice damage. 
• Tearing off the old roof and starting with a clean deck before reroofing may result in a smoother finished roof system.

Although there is added cost to these advantages, each lessens the likelihood that the validity of the manufacturer’s shingle warranty will be impaired. If the old roof is torn off, your contractor should be responsible for the clean-up and disposal of the old shingles, but make sure your contract states this clearly.

If you do plan to reroof over existing shingles, first check if your local building codes limit the number of roof layers that can be applied to a residence in your area. Your contractor should know the pertinent code requirements.

4. Why is it said that a roof should breathe? How can you determine if the roof is properly ventilated?

When contractors say a roof should breathe, they are usually referring to the ventilation system beneath the roof deck.

Most shingle warranties require a lot of ventilation– as much as “one square foot of net free ventilation area for each 150 square feet of floor space to be vented; or one square foot per 300 square feet when both ridge and soffit ventilators are used.”

An effective ventilation system will help:

• reduce attic heat build-up; 
• reduce attic moisture and condensation; 
• prevent weather infiltration, i.e., drifting snow, wind-driven rain; and, 
• prevent ice dam build-up (see the following question for ice dam discussion).

Even if you feel you’ve had satisfactory ventilation performance with your old roof for as long as 20 years, it might be necessary to add ventilation with your new roof to meet the standards mentioned previously.

5. What function does shingle underlayment serve?

An underlayment, commonly known as roofing felt, will:

• Protect the roof deck from moisture prior to shingle application; and, 
• Provide a degree of back-up protection in the event water gets under roofing shingles.

Some local building codes and U.L. standards require that a shingle underlayment be installed. Ask your contractor if this is the case in your area. Also, some manufacturers offer a special underlayment product which prevents leaks caused by water back-up from ice dams–a common condition in many winter snow areas. Protection against ice dams can be obtained by using a waterproofing shingle underlayment at the eaves or lower edges of the roof, in addition to installing adequate ventilation and proper insulation in the attic floor. (See our â€œProtecting Your Home From Ice Dams” brochure for more information.) Ask your contractor about these specialized underlayments.

CONCLUSION

We hope this brochure has provided you with some insightful information regarding the reroofing process. Our intention is not to overwhelm you with information, but rather offer you a reliable resource for easy reference. If you have any questions or comments about this brochure, we would be happy to hear from you. In addition, if you did not receive our â€œChoosing a Professional Roofer” brochure or if you would like any other literature on specific products, please write or call us at:

The CertainTeed Home Institute
P.O. Box 860 
Valley Forge, PA 19482 
or call 1-800-782-8777

Also visit us at
www.certainteed.com

Protecting Your Home From Ice Dams


WHAT ARE ICE DAMS?

Ice dams are formed when heat from the inside of a home escapes into the attic and warms the roof decking during the winter. This heat, combined with heat from the sun, can melt snow on the roof. Melting snow on the upper roof and in the valleys then runs down toward the eaves as water. When it reaches the cold eaves and gutters it refreezes. The continual thaw and re-freeze process creates ice dams. The result is water backing up under the roof shingles or behind fascia boards where it can soak through the roof decking or wall sheathing, causing damage to attics, ceilings and walls.

ICE DAM DEFENSE

There are three ways to defend against the damage ice dams cause: insulation, ventilation and water-proofing shingle underlayment. All three work together. Insulation keeps heat from escaping from your home’s living space into your attic. Ventilation removes the heat and helps keep the roof deck evenly cool to help prevent snow from melting on the roof. Finally, waterproofing shingle underlayment, such as WinterGuard™, is laid across the roof before roof shingles are applied. WinterGuard is warranted against leaks from dams that do form on the roof. With existing roofs, waterproofing shingle underlayment is only an option if you remove the existing shingles or are building a new addition. Regardless, increasing the insulation R-value in the attic is always possible and ventilation can usually be added to your attic easily

.

INSULATION

An attic insulated to today’s energy standards with fiber glass insulation minimizes heat escape through the ceiling, virtually eliminating the possibility of snow melting and refreezing at the base of the roof. If your home was built before 1980, chances are it needs more attic insulation. The amount of insulation your house should have will vary depending on where you live, how your house is built and many other factors including your lifestyle. Insulation levels are recommended by geographic zones and are stated in R-values. R-value is the resistance to heat flow of a material. The higher the R-value the greater the insulating power. The following map and chart indicate recommended levels of insulation by geographic area.

R-values on the chart represent CertainTeed recommendations for meeting today’s energy standards. Department of Energy thermal recommendations and the Council of American Building Officials Model Energy Code provide the basis for CertainTeed’s insulation recommendations.

VENTILATION

The second thing to look for in your attic is the amount of ventilation that you have. It is important to have ventilation in the attic so any heat lost from the interior of the home is drawn up and out of the attic. Adequate attic ventilation will help the roof deck stay cool. Another benefit of having your attic ventilated is that it allows for moisture that rises into the attic from things such as bathing, cooking and the laundry to escape. Unchecked moisture can promote mold, mildew, and wood rot. There are two common ways to ensure that excess moisture or heat can escape to the outside. One way is to use a power or mechanical ventilation system. The other way is through a natural or static ventilation system. A power ventilator is an electric powered fan installed at the roof or gable that runs by a thermostat or humidistat when the attic needs ventilation. Natural or static ventilation systems consist of simple vent or covered openings in your attic. These are typically ridge vents, gable, eave, or roof vents. Many ventilation experts agree that externally baffled ridge vents combined with vented soffits are a very effective method for ventilating an attic. Where older construction doesn’t permit ridge and soffit ventilation, powered fans can be a good alternative. A properly designed ventilation system must have both intake vents in the soffit or eaves at the lower part of the attic, and exhaust ventilation such as ridge vents high in the attic at or near the ridge. Typically, cooler dryer outside air enters through eave vents near the attic floor, forcing existing moisture-laden or heated air out through vents placed high on the roof or gable. By ensuring proper insulation and ventilation, you will run less risk of the formation of ice dams and you will substantially reduce the likelihood of damaging your attic components.

WATERPROOFING UNDERLAYMENT

If you are building a new home, or reroofing an older home, in addition to the points on insulation and ventilation mentioned above, you should insist that waterproofing shingle underlayment be installed before your roof shingles are applied. As mentioned earlier; it is completely resistant to water and, as such, is a critical last line of defense against leaks, preventing backed up water from getting into your new home wherever it is applied. CertainTeed WinterGuardâ„¢ is warranted to prevent water penetration for the warranted life of the new asphalt shingles applied over it (up to a maximum of 30 years). While shingle underlayment does not prevent the formation of ice dams, it will prevent backed up water from getting into the house. Discuss shingle underlayment placement with your builder. However; as a guide, the CertainTeed Home Institute recommends that it be applied:

• Under metal flashing and counter flashing at every roof penetration. 
• In areas where roof pitches change, in valleys, at joints at building additions, and at water stops behind chimneys. 
• Along the eaves and at short cornice projections.

SPECIAL CASES

Many new homes feature cathedral or vaultedceiling roofs and skylights. Both present special cases for insulation that the CertainTeed Home Institute recommends you discuss carefully with your builder. Insulation manufacturers like CertainTeed have created high-performance fiber glass batts that are designed specifically for cathedral ceilings to provide higher R-values per inch than standard fiber glass batts. In the case of skylights, quality workmanship and attention to detail are important in preventing ice dams and condensation which often lead to leaks. To avoid problems, make sure your builder properly insulates around the skylight and uses a moisture retarder to prevent condensation. In addition, applying waterproofing shingle underlayment around the skylight opening is recommended. For more information on any of these products, write to:

CertainTeed Home Institute
P.O. Box 860 
Valley Forge, PA 19482 
or call 1-800-782-8777 
Also visit us at 
www.certainteed.com

Selecting a Product

Selecting roofing shingles is no different than purchasing a major home appliance or even a new car. You should investigate your options carefully, comparison shop, and weigh the costs against features and benefits desired.

1. What's the difference between an architectural or designer shingle and a standard shingle?

Since the early 1900’s, the three-tab or strip shingle was the standard composition shingle installed in single-family residences. These products come with 20, 25, and 30-year warranty coverage. Color is about the only appearance differentiation in this class of shingle.

Many people use an architectural or disigner shingler when remodeling their home.  These are a double laminated shingle that has the appearance of cedar shake. These products come with 30, 40, 50, and many with lifetime warranties.

Other important innovations in architectural shingles include the Super Shangle and Super Shake styles. Today, the architectural shingle class is running away with the market. Warranties range up to 40 years and even lifetime. Color is no longer the only choice to make. The many textures, forms, and designs of architectural shingles in the marketplace can result in a major aesthetic upgrade for your home.

Ask Citi Roofing, Co. to show you a Good, Better, and Best selection of products. Shingles are not just for keeping out the rain anymore.

2. What type of warranty should I look for? Aren’t they all the same?

Warranties usually range from 20 to 40 years.

  • Look for manufacturers’ warranties that cover materials and labor in the first three to five years after application on any grade of roofing shingle.

  • Carefully review the manufacturer’s warranty stipulations about proration and transferability.

  • Note the contractor’s guarantee of performance. Contractors’ guarantees are usually for one to five years on the average.


3. What does the U.L. fire resistance rating for a shingle mean?

The Underwriters Laboratories (U.L.) ratings signify that the shingles were manufactured to pass a certain set of standards to qualify as fire resistant.

Organic shingles carry a U.L. Class C fire resistance rating. Fiberglass shingles carry a U.L. Class A fire resistance rating. Either is appropriate for residential applications.


What Are Ice Dams?

Ice dams are formed when heat from the inside of a home escapes into the attic and warms the roof decking during the winter. This heat, combined with heat from the sun, can melt snow on the roof. Melting snow on the upper roof and in the valleys then runs down toward the eaves as water. When it reaches the cold eaves and gutters, it refreezes. The continual thaw and re-freeze process creates ice dams. The result is water backing up under the roof shingles or behind fascia boards where it can soak through the roof decking or walls heating, causing damage to attics, ceilings and walls.

ICE DAM DEFENSE
There are three ways to defend against the damage ice dams cause: insulation, ventilation and waterproofing shingle underlayment. All three work together. Insulation keeps heat from escaping from your home’s living space into your attic. Ventilation removes the heat and helps keep the roof deck evenly cool to help prevent snow form melting on the roof. Finally, waterproofing shingle underlayment is laid across the roof before roof shingles are applied.

INSULATION
An attic insulated to today’s energy standards with fiberglass insulation minimizes heat escape through the ceiling, virtually eliminating the possibility of snow melting and refreezing at the base of the roof.

If your home was built before 1980, chances are it needs more attic insulation. The amount of insulation your house should have will vary depending on where you live, how your house is built and many other factors including your lifestyle. Insulation levels are recommended by geographic zones and are stated in R-values. R-value is the resistance to heat flow of a material. The higher the R-value, the greater the insulating power.

VENTILATION
The second thing to look for in your attic is the amount of ventilation that you have. It is important to have ventilation in the attic so any heat lost from the interior of the home is drawn up and out of the attic. Adequate attic ventilation will help the roof deck stay cool. Another benefit of having your attic ventilated is that it allows moisture that rises into the attic from things such as bathing, cooking and laundry to escape. Unchecked moisture can promote mold, mildew and wood rot.

There are two common ways to ensure that excess moisture or heat can escape to the outside. One way is to use a power or mechanical ventilation system. The other way is through a natural or static ventilation system. A power ventilator is an electric powered fan installed at the roof or gable that runs by a thermostat or humidistat when the attic needs ventilation. Natural or static ventilation systems consist of simple vent or covered openings in your attic. These are typically ridge vents, gable, eave or roof vents.

A properly designed ventilation system must have both intake vents in the soffit or eaves at the lower part of the attic, and exhaust vents such as ridge vents high in the attic at or near the ridge.

WATERPROOFING UNDERLAYMENT
If you are building a new home or reroofing an older home, in addition to the points on insulation and ventilation mentioned above, you should insist that waterproofing shingle underlayment be installed before your roof shingles are applied. While shingle underlayment does not prevent the formation of ice dams, it will prevent backed up water from getting into the house. Discuss shingle underlayment placement with your builder.

  • Under metal flashing and counter flashing at every roof penetration.

  • In areas where roof pitches change, in valleys, at joints at building additions and at water stops behind chimneys.

  • Along the eaves and at short cornice projections.

Choosing a Professional Roofer

PoorBest Re-roofing is a process you may not be familiar with until it becomes time to replace the roof on your own home. And even then, there’s a lot to learn about which products to use and what procedures best meet your individual roofing needs. Therefore, it’s vital to know that you can rely on the roofing contractor you choose to give you good advice about those products and procedures that may be new to you. The key is to find the right roofing contractor for your job. That’s why CertainTeed has developed this guide to selecting a roofing contractor: The questions contained in this brochure are designed to help you determine the reliability, reputation and experience of a contractor; as well as his dedication to providing you with the best roof possible. A top-notch, professional roofing contractor will be only too happy to supply you with answers to these questions. And just as it makes good business sense to see several bids on your roofing job, it also makes good sense to ask several different contractors these questions. We’ve also outlined some important points to consider as you evaluate the terms of your proposed job contract. Being confident you’ve selected the right roofing contractor will help assure that you have a quality roof overhead and that your hard-earned money has been wisely spent.

Seven Questions to Ask Your Roofer

At CertainTeed, we suggest that you evaluate your roofer as carefully as you would a doctor or lawyer. It is certain that you will want a roofing contractor who employs capable applicators to install the shingles. It is also clear that you will need to look closely at the proposal offered, the products selected, and the price/value relationship of the entire package. But what criteria can you use to decide if the contractor is a true professional who will stand behind his work? While there is not a single, clear-cut answer, there are a number of indicators that you can look for when going through the evaluation process.

Interview the Contractor

You cannot choose a professional roofer by looking at an estimate and comparing prices. Allow yourself an hour, more or less, to sit down with each contractor. You might be speaking with a salesperson or even the owner. Both of you need time to ask questions and explore the possibilities. You will be surprised at how many options you have. Good contractors take pride in their work, and so should the salesperson representing the company.

• The salesperson should show pride and enthusiasm in discussing other jobs. 
• The salesperson should be knowledgeable about other jobs (which shows his amount of involvement in the actual work).

The Seven Questions to Ask

1. What is the full name and address of the company?

Getting the complete address of the company can be an important factor in determining a company’s time in business. If a post office box is given, ask for a full street address as well. Try to hire a contractor that has an office nearby. The likelihood of quicker service is greater if the company is based near your home.

2. Does the company carry insurance?

A contractor should carry comprehensive liability insurance and workers’ compensation insurance to protect you in the event of a roofing accident. This can be verified by asking to see the contractor’s certificates of insurance (workers’ compensation and general liability). Let the contractor know you want current certificates sent to you by the insurer before the job is started. Contractors may also carry other kinds of insurance including health, life and auto insurance. Bland assurances of insurance coverage may refer to these. Don’t be confused. Ask for proof of general liability and workers’ compensation coverage for roofing projects. Worker Accidents. Be aware that if a worker is injured on your property, the homeowner might be held liable for all costs unless the employee is covered by workers’ compensation insurance. Hospital bills for serious accidents can be extraordinarily expensive. Contractors who carry insurance and follow safety guidelines on fall prevention endure higher job overhead costs. These expenses could be the cause of price variations between contractors who follow the standards versus those who ignore them. Uninsured Contractors. Roofers who do not carry insurance will most likely be cheaper to hire as they do not have the large insurance premiums to pay. Workers’ compensation premiums can increase wage costs from about 20% to as much as 100%, depending on the state. 2 There are a variety of reasons why full insurance may not be carried by a contractor, such as:

  • Not a full-time contractor 
  • Operates as a partnership or self-employed without employees 
  • New in the business 
  • Can’t afford insurance premiums 
  • Doesn’t stand behind work It is up to you to determine if it is worth the risk to hire a contractor who does not carry insurance.

3. Is the company a licensed or credentialed contractor?

When you pose this question, you are, in effect, asking if the contractor is licensed by your state and/or city. Not all states require contractors to be licensed. If your state does license contractors, then he might have had to pass a written examination in his specialty, although few licenses make this a requirement. A number of cities also require professional licensing. Check with your local licensing authority for details. A contractor may also answer this question by telling you he has a business license. However, a business license is a tax requirement only and is not directly relevant to the contractor’s competence. Several roofing manufacturers offer a variety of programs to professional contractors that establish their credentials as a knowledgeable roofing company. Homeowners can view a contractor’s credentials as another indicator of their degree of knowledge, professionalism, and dedication to the roofing trade.

4. How long has the company been in business?

Needless to say, longer is usually better. Under three years may signal an unstable business or one low on the learning curve. On the other hand, everybody has to start some time. References will be helpful to double check any business, and are especially important when dealing with a new business. A newer business may have a great future but it is only reasonable to be more careful when considering its referrals. The failure rate of small businesses in the first three years is very high.

5. Will the company provide referrals or references from previous jobs?

• Ask for photos of completed work, if available. Keep in mind, however, that many roofers will not have photos. 
• Request a list of 10 names and phone numbers of recent customers (last 12 months). It is not necessary to check all 10, but you will be able to pick randomly from the list those you do call.

6. What is the company’s workmanship warranty?

Typically, contractor workmanship warranties are for one year or more. Longer warranties are not necessarily more valuable than shorter warranties. The length of the warranty is less important than the intent and ability of the roofer to stand behind his warranty. That is best evaluated using customer referrals. Ask his customers specifically for information about these four things:

1) Did he perform his work on a timely basis? 
2) Was he responsive when asked for information and changes? 
3) Did he act as if he cared about the customers interests? And finally, 
4) would you call the company trustworthy? The roofer will warrant his workmanship. The manufacturer, on the other hand, warranties the roofing material against defects in manufacturing. Thus, two warranties will cover the shingle roof system. Understand them both. Ask for a copy of the manufacturer’s warranty pertaining to the specific shingle products you are considering. Usually, problems of either workmanship or material show up very quickly. Therefore, the near-term warranty given by the contractor or manufacturer is more important than the warranty coverage during the later years of the warranty. Even if problems of workmanship arise after the workmanship warranty has lapsed, a reliable contractor usually will want to stand behind his work.

7. What is the company’s track record for solving customer complaints?

• Try to find out how your contractor handles problems when they do arise. Request a referral from a job that involved a complaint. 
• Ask the contractor if he has ever lost a job-related court case. 
• Ask if his contractor’s license has ever been suspended and why. Also, in talking to the appropriate authorities, such as the Better Business Bureau and licensing departments, find out if any complaints have been filed against the contractors whom you have interviewed. Many contractors in business for any length of time have been involved in a dispute. Ask how the dispute was resolved, to test your contractor’s reputation.

Evaluating the Contract

Before you get to this stage, you will have received from the roofer either a job proposal or an estimate. Estimates and proposals can be very different approaches to your job.

What is an Estimate?

To simplify, an estimate will typically offer a single price, a generically described product, a color and no options. This is traditional and legitimate. But it isn’t consumer-friendly.

What is a Proposal?

Simply put, a proposal is a tentative agreement for a project. It offers a choice of products by brand name, prices, services and even designs. Many other provisions may also be included such as change order conditions and financing options. The homeowner should expect three product choices. These could be presented in the typical range of good, better and best. Appropriate product literature and samples should also be offered. In conclusion, a proposal is consumer-friendly.

Details, Details!

Most contracts for roofing work are simple and straightforward. The larger or more experienced contractors may have longer, more detailed contracts. Regardless of the form of the agreement, you should read all of the specific items in the contract carefully. Misunderstandings are more often the cause of contract disagreement rather than actual dishonesty or incompetence. It is in your interest that certain items which are important to you be stated in writing in the contract. The following are some of the basics that should be covered:

Compliance with local codes and ordinances.

Will they be observed? Are permit costs included? Who will obtain the permit? What about provisions for posting zoning notices? Have inspections been planned?

Product choices

Have you been offered a choice of shingles? Are they identified by brand and manufacturer name? Is there a clear reference to the warranty which will cover the shingles to be applied? Is the manufacturer’s name for the color of the shingle you are buying stated in the contract? Do you understand the difference in the aesthetics from one shingle to another (including not only color but also texture, style, construction, reinforcement and UL ratings)?

Scheduling

Start and stop dates are difficult to pin down due to the unpredictability of the weather. But you can control exceptions. For instance, negotiate a “no-later-than” clause. Be reasonable, but do make it clear that these terms will be enforced if necessary. If early completion is important, offer an award for completion by an early date in addition to a no-later-than clause. NOTE: Some state laws require a no-later-than clause.

Right-to-Rescind

This clause establishes a time period in which the homeowner can cancel the contract without penalty. Some states require such a clause in contracts. Check with your local authorities. Three days is usually the time period given for a right-to-rescind without penalty. If the homeowner cancels the job after the right-to-rescind period has elapsed, then the contractor may request a certain dollar or percentage value of the contract in return.

Manufacturer’s warranty specifications

Confirm that the Agreement states that all workmanship will conform to the requirements of the manufacturer’s warranty and installation instructions. Especially take note that this includes ventilation requirements, fastener requirements, low slope installation terms and ice dam protection. All such terms are normally found on the shingle packaging, or will be found on manufacturer’s literature available from suppliers.

Contractor’s workmanship warranty

Make sure this is clearly noted in the contract.

Clean-up

Call for a daily clean-up of the premises. This becomes very important if shingle tear-off is necessary.

Payment terms

Schedule, terms and method of payment should be written out fully with no room for misunderstandings.

Preliminary inspection

Finally, agree to an inspection before the job with the job supervisor. Establish the condition of the property before any work is done. Take special care to list the conditions of landscaping and equipment located under or near the roof eaves. Do not be unreasonable on your expectations. It is not possible to reroof a house without some damage to landscaping. Discuss and agree on what is reasonable. Prepare a checklist as you go and co-sign it, indicating that both parties understand the present condition of the property. A thorough inspection after the job will determine if any valid property damage claims exist.

Insider Tips

Understanding the Contractor

This pamphlet serves as a guide to shopping for a good contractor and negotiating a good contract. However, you should keep in mind that your contractor is also shopping. A contractor is shopping for good jobs that will make a fair profit and bring future referrals. Many contractors have had experiences with unreasonable or dishonest homeowners. Therefore, they look for warning signs of customer problems during the initial job interview. Show the contractor that you are an informed consumer who has both your and his best interests in mind.

Getting a Roofing Contractor to WANT your Job

Many homeowners have been mystified by the seeming lack of interest and response from contractors when they receive a call for a job. Here’s how you can get a roofer to respond to your call: • When you call a roofer, tell him you are shopping around, but are only interviewing three contractors, not 10.

• Call contractors in the general vicinity. Roofers prefer to work close to home, just like everyone else. 
• Tell the contractor you call that you are not looking for the lowest bid, but rather the best value. And ask for a Good-Better-Best proposal. 
• If you have seen work by a contractor in your neighborhood and you liked it, or if someone referred a contractor to you, call him. And when you do call, mention how you received the contractor’s name.

By following these tips you can help a roofer to determine that you are a good prospect and worth his effort.

Local Information

There are a number of organizations and institutions that you can contact when you need additional help or information about reroofing. Unfortunately, it is not possible to predict which will be the most useful in any given location. Consider these sources:

• Local Better Business Bureau 
• City, county and state licensing authorities
• Local roofing trade associations, whose members are actual contractors, should be active in policing their trade and can be excellent sources of information.

We hope this brochure will help you in selecting a professional roofer. If you have any questions or comments about this brochure, we would be happy to hear from you. We also have developed a number of other educational materials on re-roofing, including our “Homeowner’s Guide to Re-roofing Products, Procedures and Problems,” and a consumer brochure on manufacturers’warranties entitled “What About the Warranty?” If you would like a copy of these brochures or any other literature on specific types of products, or to find contractors in your area who qualify for CertainTeed credentials, please write, or visit www.certainteed.com or call us at:

The CertainTeed Home Institute
Roofing Products Group 
P.O. Box 860 
Valley Forge, PA 19482 
(800) 782-8777