How to Test for Mold

Look for telltale characteristics., Check the basement., Check the utility room., Check small enclosed spaces., Check your windows., Check places recently damaged by water., Check shower curtains., Check ceiling corners., Check air ducts and vents...

28 Steps 7 min read Advanced

Step-by-Step Guide

  1. Step 1: Look for telltale characteristics.

    Mold often has a fuzzy appearance but can also look like a stain if it’s growing on a wall or furniture.

    Its most common colors are black green, brown, or white.

    Mold can feel like cotton, leather, velvet, or sand paper.

    It usually gives off a musty or earthy odor., This should be the first place you look.

    Its underground location makes it especially vulnerable to moisture and humidity buildup.

    After each heavy rain, look for and immediately treat any water seepage.Check the following spots:
    Baseboards Walls, especially where they meet the ceiling Behind and under appliances, especially the washer and dryer , Look in and around the clothes dryer duct for mold growth.

    If it’s not properly ventilated, it can trigger a build-up in humidity in the room.

    Make sure the duct is vented toward the exterior of the house., Darkness and moisture create ideal conditions for the spread of mold.You should check:
    Under sinks, especially if they sit on top of cabinets Closets, especially if they don’t receive proper ventilation., If your house isn’t properly insulated, windows could accumulate condensation year-round.

    Look for mold growth around each individual pane and along the frames., Inspect the baseboards in the basement and first/ground floor if your house recently flooded.

    Tear out all carpeting in these areas.

    If you recently experienced heavy rain, look for water stains in the attic and on the upper-story living areas.If a pipe recently burst, treat all water-damaged areas as if they had been flooded. , Dirt and grime that washes off your body has a tendency to mix with shampoo and soap residue.

    This mixture ultimately collects on shower curtains.

    Make sure the bathroom is well lit.

    Spread out the shower curtain to check the entire surface.

    Use a magnifying glass to check for small patches of mold that you could otherwise miss. , The corners where your walls meet the ceiling are prime locations for mold growth because they trap water from roof leaks.

    Check for growth and accumulation in all four corners of each room.

    If your wallpaper is peeling at the ceiling juncture, check behind it for mold growth., Fluctuations between heating and air conditioning cause moisture buildup on cooling coils and in drain pans.

    Remove the vent plate from the duct and inspect it closely.

    Turn on the lights or use a strong LED flashlight to easily catch mold clusters.

    Check the duct for as far as your eye can see. , In-home testing kits come equipped with their own instruments and instructions.

    Follow the kit's directions.

    Submit the sampling to a local lab.

    If you see mold in a visual inspection, a testing kit isn’t necessary.These kits can be difficult to use, and their results can be unreliable.

    Use them only as a last resort if other options aren’t available. , A borescope can be helpful for inspecting spaces between walls.Drill a small hole into a wall recently affected by water or moisture.

    Slowly insert the fiber optic cable end through the hole.

    Check the monitor for signs of mold.

    Continue to move slowly as you probe deeper into the area.

    Borescopes distort the size and color of mold on the monitor.

    If you find areas of discoloration inside the wall, contact a professional for a second opinion.

    You can also use a borescope to inspect air ducts, but there are drawbacks.

    The instrument only lets you see so far into a duct.

    If the duct makes a sudden 90-degree turn, you won’t be able to see beyond that turn. , They have instruments for mold detection that aren’t available to the general public.

    Get estimates from several inspectors to make sure you get a fair deal.

    Contact former customers for reviews and possible complaints.

    Consult your state's contractor licensing board to ensure your potential inspector is licensed.

    Make sure the inspector works with a lab accredited by the Environmental Protection Agency (EPA) or American Industrial Hygiene Association (AIHA)., Cover your mouth and nose with an N-95 respirator to avoid breathing in spores.

    Wear elbow-length rubber or latex gloves to protect your hands from mold and cleaning materials.

    Cover your eyes with goggles to protect them from airborne spores., Mix equal parts water and detergent or bleach.

    Dip a scrub brush into the mixture and remove the mold.

    Dry the area completely when you’re finished., If you noticed any leaking pipes or water seepage in your inspection, deal with it immediately.

    Call a professional plumber to repair leaking or sweating pipes.

    Fill in any spaces between pipes and walls with caulk or Icynene insulation., Use caulk to seal cracks around your windows, doors, and at critical junctures where the walls meet the floor and the ceiling.

    Apply caulk or weather stripping to your windows, especially between the frames and panes.

    Dry the area completely.Don’t caulk or paint any surfaces until the mold is completely removed.

    If you’re not comfortable doing these repairs, hire a professional. , Unless you’re trained to remove mold from air ducts, call a professional.

    This is especially crucial if you notice mold growth in more than one room or if your mold problem keeps recurring despite your best efforts.

    Search online for local professionals or ask your local health department for a recommendation., If you notice mold on carpeting, ceiling tiles, and other porous surfaces, remove and discard them.

    The mold makes them unfit for recycling.

    Ask your local waste management whether they consider it hazardous waste., If you find mold growing on books, heirlooms, or sentimental objects, consult a professional for help.

    Ask a senior librarian or museum conservator to refer you to a trusted expert.

    You could also do online searches for professionals who repair and preserve rare objects.

    Make sure you get the expert’s references.

    If possible, hire someone who is accredited by a professional organization like the American Institute for Conservation (AIC) or the American Library Association (ALA)., Keep the humidity level in your home between 30 and 50 percent.

    Open the windows on days when it’s not humid.

    This will allow fresh air to circulate and inhibit mold growth.

    If you live in a humid climate, run a dehumidifier in the rooms most prone to moisture., These areas are already prone to humidity.

    Carpets can trap moisture under their surface, even without flooding or water seepage.

    If your basement or bathroom isn’t carpeted, leave the floors bare.

    Use removable, washable mats to avoid slip hazards., This is a great investment if you live in a flood-prone area.

    Water that seeps into the basement collects in a sump basin and is pumped outside.

    Unless you are a licensed home improvement contractor, call a professional to install one.

    Choose a sump pump with the following specs:
    Cast iron core Alarm that sounds when the water level gets too high Mechanical switch Submersible pump No-screen intake design Impellor that can deal with objects of
    0.5 inches (1.3 cm) in diameter., When you cook, turn on the exhaust fan over the stove to catch water vapor.

    Use the fan in the bathroom as you shower to reduce condensation cause by steam.

    Even if you take cooler showers, run the exhaust fan for good measure.

    Let the fans in each room run until all steam has been eliminated., Install them in the basement and in closets.

    Clean each dehumidifier regularly.

    Follow the manufacturer’s instructions closely for best results., Use a clean dry towel or a squeegee to remove any leftover water droplets.

    Make sure the curtain is completely dry.

    Do this after the last shower of the day to prevent moisture buildup., Water can pond around the foundation of your house and push moisture into the interior.

    Landscape the area around the foundation to slope downward and away from the foundation.

    Add extensions to downspouts to direct rainwater at least 5 feet (1.5 m) away from the foundation., Apply spray-on Icynene foam to the ceiling of your attic.

    The foam forms a water-tight seal as it dries.

    Avoid fiberglass and hard foam insulation.

    They can separate from their surfaces and allow moisture to seep in.

    Wet spray-applied cellulose insulation is also prone to mold., Check all problem areas or potential problem areas for mold (re)growth.

    Monitor all sealed leaks and cracks after heavy rains or floods.

    Otherwise, recheck your home thoroughly every six months.
  2. Step 2: Check the basement.

  3. Step 3: Check the utility room.

  4. Step 4: Check small enclosed spaces.

  5. Step 5: Check your windows.

  6. Step 6: Check places recently damaged by water.

  7. Step 7: Check shower curtains.

  8. Step 8: Check ceiling corners.

  9. Step 9: Check air ducts and vents.

  10. Step 10: Use an in-home mold testing kit.

  11. Step 11: Use a borescope.

  12. Step 12: Hire a professional mold inspector.

  13. Step 13: Protect yourself.

  14. Step 14: Clean hard surfaces.

  15. Step 15: Fix all leaks.

  16. Step 16: Seal small openings.

  17. Step 17: Have your air ducts cleaned.

  18. Step 18: Dispose of surfaces that absorb moisture.

  19. Step 19: Seek assistance.

  20. Step 20: Reduce humidity levels.

  21. Step 21: Remove carpeting from the basement and bathroom.

  22. Step 22: Install a sump pump.

  23. Step 23: Run exhaust fans.

  24. Step 24: Use dehumidifiers.

  25. Step 25: Wipe down the shower curtain.

  26. Step 26: Prevent water from pooling.

  27. Step 27: Use the right insulation.

  28. Step 28: Inspect your home regularly.

Detailed Guide

Mold often has a fuzzy appearance but can also look like a stain if it’s growing on a wall or furniture.

Its most common colors are black green, brown, or white.

Mold can feel like cotton, leather, velvet, or sand paper.

It usually gives off a musty or earthy odor., This should be the first place you look.

Its underground location makes it especially vulnerable to moisture and humidity buildup.

After each heavy rain, look for and immediately treat any water seepage.Check the following spots:
Baseboards Walls, especially where they meet the ceiling Behind and under appliances, especially the washer and dryer , Look in and around the clothes dryer duct for mold growth.

If it’s not properly ventilated, it can trigger a build-up in humidity in the room.

Make sure the duct is vented toward the exterior of the house., Darkness and moisture create ideal conditions for the spread of mold.You should check:
Under sinks, especially if they sit on top of cabinets Closets, especially if they don’t receive proper ventilation., If your house isn’t properly insulated, windows could accumulate condensation year-round.

Look for mold growth around each individual pane and along the frames., Inspect the baseboards in the basement and first/ground floor if your house recently flooded.

Tear out all carpeting in these areas.

If you recently experienced heavy rain, look for water stains in the attic and on the upper-story living areas.If a pipe recently burst, treat all water-damaged areas as if they had been flooded. , Dirt and grime that washes off your body has a tendency to mix with shampoo and soap residue.

This mixture ultimately collects on shower curtains.

Make sure the bathroom is well lit.

Spread out the shower curtain to check the entire surface.

Use a magnifying glass to check for small patches of mold that you could otherwise miss. , The corners where your walls meet the ceiling are prime locations for mold growth because they trap water from roof leaks.

Check for growth and accumulation in all four corners of each room.

If your wallpaper is peeling at the ceiling juncture, check behind it for mold growth., Fluctuations between heating and air conditioning cause moisture buildup on cooling coils and in drain pans.

Remove the vent plate from the duct and inspect it closely.

Turn on the lights or use a strong LED flashlight to easily catch mold clusters.

Check the duct for as far as your eye can see. , In-home testing kits come equipped with their own instruments and instructions.

Follow the kit's directions.

Submit the sampling to a local lab.

If you see mold in a visual inspection, a testing kit isn’t necessary.These kits can be difficult to use, and their results can be unreliable.

Use them only as a last resort if other options aren’t available. , A borescope can be helpful for inspecting spaces between walls.Drill a small hole into a wall recently affected by water or moisture.

Slowly insert the fiber optic cable end through the hole.

Check the monitor for signs of mold.

Continue to move slowly as you probe deeper into the area.

Borescopes distort the size and color of mold on the monitor.

If you find areas of discoloration inside the wall, contact a professional for a second opinion.

You can also use a borescope to inspect air ducts, but there are drawbacks.

The instrument only lets you see so far into a duct.

If the duct makes a sudden 90-degree turn, you won’t be able to see beyond that turn. , They have instruments for mold detection that aren’t available to the general public.

Get estimates from several inspectors to make sure you get a fair deal.

Contact former customers for reviews and possible complaints.

Consult your state's contractor licensing board to ensure your potential inspector is licensed.

Make sure the inspector works with a lab accredited by the Environmental Protection Agency (EPA) or American Industrial Hygiene Association (AIHA)., Cover your mouth and nose with an N-95 respirator to avoid breathing in spores.

Wear elbow-length rubber or latex gloves to protect your hands from mold and cleaning materials.

Cover your eyes with goggles to protect them from airborne spores., Mix equal parts water and detergent or bleach.

Dip a scrub brush into the mixture and remove the mold.

Dry the area completely when you’re finished., If you noticed any leaking pipes or water seepage in your inspection, deal with it immediately.

Call a professional plumber to repair leaking or sweating pipes.

Fill in any spaces between pipes and walls with caulk or Icynene insulation., Use caulk to seal cracks around your windows, doors, and at critical junctures where the walls meet the floor and the ceiling.

Apply caulk or weather stripping to your windows, especially between the frames and panes.

Dry the area completely.Don’t caulk or paint any surfaces until the mold is completely removed.

If you’re not comfortable doing these repairs, hire a professional. , Unless you’re trained to remove mold from air ducts, call a professional.

This is especially crucial if you notice mold growth in more than one room or if your mold problem keeps recurring despite your best efforts.

Search online for local professionals or ask your local health department for a recommendation., If you notice mold on carpeting, ceiling tiles, and other porous surfaces, remove and discard them.

The mold makes them unfit for recycling.

Ask your local waste management whether they consider it hazardous waste., If you find mold growing on books, heirlooms, or sentimental objects, consult a professional for help.

Ask a senior librarian or museum conservator to refer you to a trusted expert.

You could also do online searches for professionals who repair and preserve rare objects.

Make sure you get the expert’s references.

If possible, hire someone who is accredited by a professional organization like the American Institute for Conservation (AIC) or the American Library Association (ALA)., Keep the humidity level in your home between 30 and 50 percent.

Open the windows on days when it’s not humid.

This will allow fresh air to circulate and inhibit mold growth.

If you live in a humid climate, run a dehumidifier in the rooms most prone to moisture., These areas are already prone to humidity.

Carpets can trap moisture under their surface, even without flooding or water seepage.

If your basement or bathroom isn’t carpeted, leave the floors bare.

Use removable, washable mats to avoid slip hazards., This is a great investment if you live in a flood-prone area.

Water that seeps into the basement collects in a sump basin and is pumped outside.

Unless you are a licensed home improvement contractor, call a professional to install one.

Choose a sump pump with the following specs:
Cast iron core Alarm that sounds when the water level gets too high Mechanical switch Submersible pump No-screen intake design Impellor that can deal with objects of
0.5 inches (1.3 cm) in diameter., When you cook, turn on the exhaust fan over the stove to catch water vapor.

Use the fan in the bathroom as you shower to reduce condensation cause by steam.

Even if you take cooler showers, run the exhaust fan for good measure.

Let the fans in each room run until all steam has been eliminated., Install them in the basement and in closets.

Clean each dehumidifier regularly.

Follow the manufacturer’s instructions closely for best results., Use a clean dry towel or a squeegee to remove any leftover water droplets.

Make sure the curtain is completely dry.

Do this after the last shower of the day to prevent moisture buildup., Water can pond around the foundation of your house and push moisture into the interior.

Landscape the area around the foundation to slope downward and away from the foundation.

Add extensions to downspouts to direct rainwater at least 5 feet (1.5 m) away from the foundation., Apply spray-on Icynene foam to the ceiling of your attic.

The foam forms a water-tight seal as it dries.

Avoid fiberglass and hard foam insulation.

They can separate from their surfaces and allow moisture to seep in.

Wet spray-applied cellulose insulation is also prone to mold., Check all problem areas or potential problem areas for mold (re)growth.

Monitor all sealed leaks and cracks after heavy rains or floods.

Otherwise, recheck your home thoroughly every six months.

About the Author

L

Lori Chavez

Brings years of experience writing about lifestyle and related subjects.

31 articles
View all articles

Rate This Guide

--
Loading...
5
0
4
0
3
0
2
0
1
0

How helpful was this guide? Click to rate: