How To Repair Mold Damage – A Homeowner’s Guide
The first step in any mold clean-up is to determine the location of the mold growth(s), and the source of the moisture. For more information on how to find your mold problem, refer to our homeowner’s guide “how to find your mold problem.

“Small area” mold clean-up

“Small areas” of mold (less than 3 patches of 10 square feet or less each) can easily be treated by anyone.  You should always wear protective equipment when cleaning mold, which should at minimum include:

Examples of “Small Areas”

  • Tile
  • Grout
  • Drywall
  • Ceiling Tiles
  • Wood Paneling
  • 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 until the mold problem has been alleviated.

To Clean Small Areas of Washable surfaces:

Scrub with UrthPRO™ and allow to dry.  Wipe with a damp cloth if cosmetically necessary and dry quickly.

To Clean Small Areas of Moldy drywall:

Wet the surface with UrthPRO™ and wipe with a clean, damp rag or cloth.  Do not over-saturate the drywall.

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 Restoration Professional.

"Moderate area" mold clean-up

If you follow the proper procedures and use the proper protective equipment, a do-it-yourselfer can easily clean up “moderate areas” of mold. “Moderate” means more than 3 patches of mold, each smaller than 10 square feet, or one or more isolated patches larger than 10 square feet but a total area smaller than 32 square feet (size of a 4 x 8 foot sheet of plywood or drywall).

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.

For Moderate Area 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 UrthPRO™.  Rinse by sponging with a clean, wet rag.  Repeat as necessary.  Dry quickly.  HEPA vacuum the surfaces that were cleaned as well as surrounding areas.

Cleaning Moderate Area Wood Surfaces

Vacuum loose mold from wood surfaces using a HEPA or externally exhausted vacuum.  Clean the surface of the wood with UrthPRO™.   Rinse with a clean, damp rag and dry quickly.  If the staining does not come off, wet the surface with UrthPRO™, then sand and vacuum the surface of the wood with a vacuum/sander combination.  It is important to vacuum at the same time to prevent mold spores from being dispersed into the air.  Clean the surface of the wood with UrthPRO™, rinse with a clean damp rag and dry quickly.  Note that wood affected by rot may need to be replaced.

Cleaning Moderate Area Concrete Surfaces

Vacuum the concrete surfaces to be cleaned with a HEPA or externally exhausted vacuum cleaner. Clean up surfaces with UrthPRO™. If the surfaces are still visibly moldy, saturate the moldy concrete surface with UrthPRO™ using a sponge or rag.  Keep the surface wet for 15 minutes. Rinse the concrete surface twice with clean water.  Dry thoroughly, as quickly as possible.

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 should be cleaned with UrthPRO™.  A mold clean-up contractor should do this.  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.

"Extensive area" mold clean-up

If your problem is greater than those discussed here, you encounter a persisting problem or see adverse health effects of family members that appear to be inside your home, you may need professional help.  Learn How To Hire A Mold Contractor

Bleach is NOT recommended for ANY mold clean-up

The presence of organic (humic) materials, the pH (acidity/alkalinity) of the water, the surface material and contact time affect the effectiveness of bleach for disinfection. Since these factors are not generally controlled, bleach cannot be relied upon for disinfection. The most compelling reason for advising against bleach is that fumes are harmful but in addition, overuse of bleach will result in increased releases of chlorinated effluents which can be harmful to the environment.



# 2011-03-24 15:19
I used 1 gallon of urthpro to kill mold along the baseboard of the wall in my basement. It seems to have worked great! I was surprised by how well the mold stains came off and the musty smell disappeared to. However, I noticed that back in my furnace room there seems to have been another leak this winter and there is alot more mold. Should I try to fix this myself? Or, should I call someone to fix it?
# UrthPRO 2011-03-24 15:24
Hi Barney,

To address your concern, we would need some more information. It will also depend on your level of comfort doing some light-to-moderate carpentry/construction.

First, you need to determine where the leak is coming from, and then how it can be properly fixed.

For now, you should clean up any visible mold to help keep the problem under control, but you should certainly assess,or have your problem assessed immediately.

If we can help further, please let us know.
# 2011-04-17 00:11
we discover a very large area down in the basement of our church had black discoloring. the men used lysol and then bleach to clean it. it was dusty and they vacumed it up. i usually use the vacuum to clean the entire upstairs. i'm concerned the next time i use it i will be putting it all over the church. they said it wasn't black mold cause, it wouldn't of cleaned up so easily. i say it was. how long do the symptoms of black mold appear. my eyes burned right away. my nose started running. i have allergies to mold and mildew already. the basement has been very stinky for a long time. can you give me some helpful advice? thanks, debbie n.
# UrthPRO 2011-04-19 14:13

You raise some good concerns about your basement and equipment.

Regardless of whether the mold in your basement was "black" mold (which is used ONLY to refer to a single type of mold called Stachybotrys chartarum), lysol and bleach are definitely NOT recommended for cleanup. The area should be contained (i.e. blocked off from the rest of the structure with some sort of plastic barrier) sprayed down with a product that is effective against mold like UrthPRO, and vacuumed with a HEPA vacuum (not a common household vacuum!).

Especially if you or any patrons have allergies to mold, your mold problem is NOT gone! You should seek professional help. If you need help finding someone in your area who is reputable and qualified to perform services, please email us and we will try and put you in touch with someone.

Thank you for your question, and we hope this information helps.
# 2011-04-17 00:15
did you get my comment i sent? not sure if it went through?
# 2011-05-20 20:29
where can i buy this urthpro, like in a store, not online?
# UrthPRO 2011-05-24 13:30
Hi Jen,

UrthPRO is available right here via Because we sell primarily to restoration and cleaning professionals, we sell directly to our customers. In the future, we may decide to pursue retail outlets, but for now it can only be found here. If you're interested in purchasing UrthPRO, you can also call us at 800-949-URTH to learn more about our customer-direct volume discounts.
# 2011-06-10 15:40
We just moved into a new home - there was evidence of past roof leaks although we were assured the roof no longer leaks. Now that we have moved in, the house seems to have a strange odor, which I think might be mold, although I have not seen any visable evidence of this. How can I check this out?
# UrthPRO 2011-06-10 15:55

Unfortunately there is no easy answer to your question, but there are some things you should look out for to help you figure out if you do in fact have a mold problem. Given that the problem area might be stemming from past leaks, start by looking in your attic (if you have one) to see if there is any discoloration or obvious growth. If you don't find anything there, you may want to bring a professional in to do an inspection. Check out to understand what an Industrial Hygienist is. If you need help finding someone in your area, email us at info (at) with your location so we can better assist you.
# 2011-06-28 03:48
We're getting our roof replaced as a first major step towards eliminating my health concerns. I don't know for sure if there's mold in the roof, but I do know it's several layers of wood, the earliest from 1941. Should my children and I move out during the removal of the old roof, or the whole replacement?
# UrthPRO 2011-06-28 04:22
Hello Sarah,

Your question is a great one, but is ultimately up to you. If you're experiencing health problems and you've identified a moldy attic as the cause, at the minimum you should ask the contractor replacing the roof to contain it from the rest of the house during renovation. That means that no air flow from the roof area should enter the rest of your home via ventilation or other means.

If a good barrier is achieved, and you don't have any other concerns within your home, then there shouldn't be any reason to move out.

It is very smart to perform maintenance on your old roof, as ignoring it could lead to serious problems in the future.

Another thing to remember as they're fixing your roof is to keep the interior of your attic space dry, and if it gets wet, to dry it out immediately and spray UrthPRO on all moistened areas to ensure that no mold is left behind. Also, DON'T CLOSE IT UP UNTIL IT'S DRY!

Hope that helps!
# 2011-07-19 07:14
Thanks for the wonderful information about molds and their health risks. I think one of the best and efficient way to avoid mold problems at home is to get one of the top rated dehumidifiers in the market. I got my dehumidifier for years and I can say that it is truly one of the best to control the humidity level at home.
# 2011-09-29 20:27
We have a sunroom added on to our house and the siding has been damaged on the outside of it. I have noticed mold growing through the crack of the paneling and along the support beam and up the other side of the support beam. It seems to be pushing through the paneling. I would love to have it professionally taken care of since I have a two year old and my husband and I both have asthma. Unfortunately we don't have the money for that. We need to take off the siding and get a better idea what we are dealing with. Is it possible that we can remove it ourselves? Will we have to replace the support beam? How will we know if we need to? Do we need to cover the entire room when we try to clean it or just the door and window that lead to our house? Any answers would be very helpful. Thanks!
# 2011-10-26 02:44
We had a bathroom painted last year that has one small window above the shower. The room gets pretty steamy when one of our kids who are in college and now working. My wife and I just noticed scattered light dark specks on the wall, we aren't certain or have any idea if this is an indication or mold as it is scattered and not condensed to any one spot. The room was a darker color prior so we are wondering if it could be paint coming through or if it is mold developing.
# 2011-10-29 01:32
where do you get UrthPRO ? Home Depot
# 2011-11-11 02:31
Hi I own an older mobile home that seems to have a problem with mold. My girlfriend rents this home from me and recently she took out two shaving kits to leave for the weekend, They were stored in a bathroom cabinet/closet and when she pulled them out there was mold on both of them. I also noticed when the last tenants moved out they left the house a mess and I cleaned it from top to bottom but here was mold on a wall in a closet. I cleaned it but didnt use any remediation products. What is the best way to deal with these areas and is there anything I can do to keep it from coming back. The home is not worth putting much money in to. Thanks Will Little
# Bruce Van Wieren 2012-02-05 12:33
I own a small single story house that has electric baseboard heat. Above each heater the drywall is developing a dark sooty covering. It washes off easily but comes back within two weeks. Also in the basement along the ceiling at the outside walls the same sooty covering is developing from the ceiling down. Nothing appears along the basement floors. The house was built in the 50's and is frame construction on a block basement. Have a dehumidifier running in the basement. Could this be mold or something else and what might be the remedy.
# Brian 2012-02-27 22:00
Coming from a disaster and damage clean up company this is a very succinct and effect list of mold resolution issues that you have compiled.
# Stacey 2012-09-25 18:06
Thanks for the help! We have some water damage in salt lake city ut because of a pipe from our washer, now my whole bedroom carpet is wet. It's starting to smell a bit but I don't see any mildew yet.
# j martin 2013-05-27 05:04
we moved into our house in oct 2012. ever since we moved in someone has been sick. people around told us the house has mold and that the crawl space was flooded in the 2010 flood in nashville tn how can we check to see if it has mold under the house. i have noticed that when it rains the floors get damp and wet looking and they seem to be warping
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