Mold spores need only a comfortable environment, food (like wood, paper, carpet, etc.), and moisture to grow. If left undetected or untreated, mold can lead to negative health effects such as allergic reactions, respiratory infections, and more. Use this checklist as a basic guide to inspect your home for signs of excess moisture and mold growth.
CAUTION: When investigating possible mold issues, you may disturb contaminated areas and, in doing so, further spread contamination into the rest of the home. This poses a serious health risk to those with compromised immune systems, asthma, or allergies; therefore, before conducting a thorough mold investigation, you may want to consult your doctor or hire a professional. If you choose to conduct this search yourself, please use appropriate safety gear as recommended by the EPA (.
Basement / Crawl Space
- Inspect ceiling, joists, and stairs for mold growth.
- Check the indoor humidity levels with a moisture meter or humidistat. If over 50%, you should consider using a dehumidifier. If you have a dehumidifier, be sure to empty and clean the drip pan regularly
- Look for peeling paint, imperfections, and discoloration as this may indicate moisture. If present, locate the source of moisture, eliminate it, and dry the area within 24-48 hours.
- Inspect the floor for foundation cracks. Keep in mind that they may lead to the exterior, so check inside and outside.
- Check that the sump pump is functioning properly and the floor drain is intact. (A sump pump is found in some basements or crawl spaces, and it is used to pump water away from the house.)
- Inspect your crawl space for moisture leaks and ensure that it is properly sealed. At a minimum, there should be a 6-8 mil. plastic, or vapor barrier, covering the soil.
Exterior / Yard
- Make sure all gutters and downspouts are intact, free of debris, and that they direct water away from the house. The downspouts should extend 6-10 feet from the foundation.
- Check for signs of water pooling on the roof or around the foundation. If present, this indicates that water is not properly draining from the roof.
- Check the slope and grade of the house to ensure that the ground slopes away from the house. The slope should be about 6 inches over 6-10 feet. The slope helps direct the water away from the foundation.
- Inspect the siding and exterior paint for peeling, chipping, or bubbling paint. Also look for visible signs of mold growing on the house.
- Inspect the roof for missing or curling shingles that could lead to indoor leaks. You may need to hire a professional to inspect the roof.
- Check that the flashing around doors, windows, joints, etc., is in good condition. (Flashing is a type of material like aluminum or steel, used around joints on roofs and walls to prevent water seeping in.)
- Make sure the outside dryer vent is not blocked or filled with debris.
- Make sure the lawn/outdoor sprinklers only spray water onto grass and not the house.
- Check to see that any plantings around your foundation are not overwatered. If you have too many plants around the foundation, you may need to remove them.
Floors, Ceilings, Windows, & Walls
- Inspect ceilings and walls for any discoloration, sagging, bowing, or wet spots. If you have a dropped ceiling, lift up the tiles and inspect the cavity.
- Check for condensation, or moisture, on the windows or walls. Condensation may be a sign of high indoor humidity.
- Look for moisture leaks or peeling drywall around window frames.
- If concerned about mold beneath carpet, lift a corner of the carpet and inspect the underside for visible mold.
- If you have vinyl wallpaper, look behind it for mold.
- If you have mold in your closet, it may be caused by poor ventilation. You will need to increase the air flow, which can be done by leaving the door open. Also, if the closet is full, remove about 1/3 of the contents.
Kitchen & Bathroom
- Inspect the caulking, grout, and tiles for damage. Repair as needed.
- Check for plumbing leaks around sinks, tubs, refrigerator, dishwasher, and showers.
- Check the exhaust fan suction with a piece of toilet paper. With the fan running, place a single sheet of toilet paper in front of the fan. If the paper stays in place, the fan is working properly.
- Check to make sure kitchen and bathroom fans vent to the outside of the house.
- Does everyone in the household turn the bathroom fan on when showering or bathing? If there isn’t a fan, then they should open the window.
- Check for mold or musty smells in cabinets, drywall, and all wood materials. You may want to hire a professional who will use a moisture meter to check moisture levels.
- Clean and empty the refrigerator drip pan.
Attic
- Check for moisture damage, leaks, and proper ventilation. Ensure that exhaust ducts direct air to the outside.
- Make sure the soffits on the underside of the eaves, or overhang, of your roof are not blocked. These provide ventilation or air flow in your attic.
- Inspect the walls, joists, and insulation for any musty smell or visible mold.
Appliances
- If not present, install a water heater drip pan. Empty and clean it regularly.
- Have your heating and cooling systems serviced by a professional twice a year. Check the coils for visible mold.
- Check water heater and washing machine water lines for plumbing leaks.
- Make sure your dryer vents to the outside your house.
Other
Other things that may be contributing to the humidity in your home are things like a large quantity of plants, large aquariums, hanging laundry inside to dry, or using an unvented heater.
Remember, anywhere you smell a musty, earthy odor or see excess moisture there is the potential for mold growth. If you find either, take immediate action. First, find the source of the moisture and then fix the problem. Remove contaminated items and clean with soap and water. Then, speed dry! Generally there is no need for a mold test. Once you identify the source of moisture and repair it, that should resolve the problem.
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Status and Revision History
Published on Dec 11, 2015
Published with Minor Revisions on Jun 12, 2017
Published with Full Review on Sep 30, 2019
Published with Full Review on Jun 30, 2021
Published with Full Review on Mar 01, 2023