Moisture and Basement Mold Problems
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           Q. We have just received 3" of rain in our Kansas home, I found the carpet in the basement wet, I saw the sheetrock walls were wet from the bottom up. Things that were in boxes in the room, leather wallet, wooden chairs, wooden end tables had mold on them. I have smelt a musty odor for some time, I don't know where the moisture is coming from or for how long (we winter in Texas). It appears to be coming from the floor...is that possible? I'm not sure what to do, or where to start or who to contact. [June 6, 2005]
         A. It is very likely that you concrete basement floor has no or a degraded or damaged moisture barrier beneath the concrete floor, enabling the water to wick up from the ground through the concrete and into your house. You can use a hidden moisture meter to scan all basement floors and walls for hidden water problems. You should consult with a basement waterproofing company, but it would be very expensive to waterproof beneath your basement floor and behind the walls. The least expensive, workable solution is to pour about 2 inch thick new concrete inner, liner walls on top of your present basement walls and floors, with adequate amounts of waterproofing compound in the concrete mix to make the concrete into an effective moisture/water barrier against outside water intrusion. As to the wet drywall, remove and discard it---cut it up at least 2 feet above the wetness to be sure you have gotten all likely mold growth growing inside the drywall. Do not replace the drywall until you have fixed the water intrusion problem. Learn the 25 steps for safe and effective mold remediation.

         Q. Our sump pump went out and the basement had water. The carpet and pad were soaked.  The drywall was wet up to 2 feet high.  A company came in and cut holes in the drywall along the bottom and said they dried it out.  I am concerned that the drywall and insulation should be taken out about 2 feet high because it has been wet about a week. The insurance company said as long as it dries it is ok.  My daughter is allergic to mold and has asthma. Is this safe? [Dec. 16, 2004]
         A. Because the drywall was wet for more than 24 hours, mold growth is probably well under way, inside, and on the back of the drywall, plus the underlying wood timbers. Your common sense suggestion to remove the drywall is very relevant, but do it at least 4 ft up from the floor, not just the two feet that were wet. What you need to prove to the insurance company is the existence of a mold problem. That is easy to do with either your hiring a Certified Mold Inspector, or by using do it yourself mold test kits from a large hardware, home improvement, or safety store , to mold test the flooded wall [using the Scotch tape lift sampling technique explained in the mold test kit instructions] and to test the basement air, the air of each room above, attic, garage, and the outward air flow from each heating/cooling duct register for the possible presence of elevated levels of airborne mold spores, in comparison to an outdoor mold control test. You may need to hire an independent insurance adjuster who works on a commission basis just for you to collect from your insurance company. Insurance companies have many angles to try to escape financial responsibility for mold damage. Whether or not you collect from insurance, to protect your daughter and the rest of your family from mold illness, you need to follow the 25 steps recommended for safe and effective mold remediation.

           Q. WOW! What a great website! I have been searching for months for answers to my questions. Thank you so much! We recently purchased a house with a beautiful finished basement. About 2 months after we settled in there was an excessive amount of rainfall over a week. Quite suddenly our basement had about an inch of water in some parts. Because it happened so quickly we have not been able to determine where it came in. We do not have a basement drain (it was sealed off when the basement was finished). Then this summer's hurricanes brought us another flood (we're in NY!) and it happened again. We threw out our carpet padding and steam cleaned our carpets as a quick and inexpensive fix so we could continue to use the space. However, after the second flood we haven't been down there as much because it seems to me that there is a dust-like odor. I am very concerned about mold and mildew. Everyone says I am crazy, "it doesn't smell, and where could the mildew be . . . everything is dry". Am I crazy? Down the road we will get ceramic tiling (thank you for the tip!) and hopefully that will help, but do you think the drywalls could have mildew/mold in them? Would adding concrete to the walls and floors be a solution for us? What does that mean for the drywalls? Thank you again - your website is extremely informative and helpful! [Nov. 19, 2004]
         A. Basement mold can easily grow into the insides of the floors and walls above. In addition, airborne mold spores from the basement mold can travel in air currents to mold cross contaminate your entire house and its heating/cooling equipment and ducts. Your first step should be to determine the extent of any mold cross contamination of your home by using do it yourself mold test kits from a large hardware, home improvement, or safety store to mold test the air of the basement, each room, attic, and the outward air flow from each heating/cooling duct register for the possible presence of elevated levels of airborne mold spores, in comparison to an outdoor mold control test.  Your next step should to do stop the water penetration of your basement. Find and re-open your basement floor drain as one way to get rid of basement water. Wetness in the basement is going to cause high humidity and mold problems even with the drain opened, but the basement floor drain will help reduce the volume of basement water intrusion and standing water. Remove all drywall, paneling, and wood to install an inside concrete liner [with adequate amounts of waterproofing compound] outside of/on top of the existing concrete walls and floors.  After you have installed the concrete floor and wall liners, install large [at least 12 inch by 12inch] ceramic tile set in waterproof-containing cement and cement grout to add an additional water barrier against water intrusion into your basement. Alternatively and usually much more expensive, you could waterproof your basement walls and foundation from the outside [digging out the dirt around your basement to get at the walls and footings].  Once you have solved the water problem, your last step is to remove mold growths and elevated levels of airborne mold spores from your home and heating/cooling system. Follow the recommended mold remediation steps.

       Q. We are finishing our basement and we would like to install carpeting within the next few days.  Our carpet store recommends using the Rubber Carpet Cushion (antimicrobial) from for the carpet padding and gluing it to the floor.  However, some say that if you use a waterproof pad such as this and the floor ever gets flooded (even with clear water from a sump pump failure), you can never thoroughly dry out the area under the pad and run the risk of getting mold.  We assume that gluing down a carpet without padding is the safest route, but the floor will feel very hard and that defeats the purpose of laying carpet in the first place.  What is your recommendation? [October 9, 2004]
         A. Carpeting and padding in a basement are NOT a good idea. Someday there will be a flooding or water problem for whatever reason, and you will have to scrape off the glued padding/carpeting to discard it [if wet for more than 24 hours, thus enabling mold to begin growing]. Your very best flooring would be large ceramic tiles installed with waterproofed cement, to make an impervious to water flooring. In addition, carpeting and padding become breeding grounds for mold growth, dust mites, bacteria contamination, and other environmental threats. Three precautions you should take if you are going to carpet anyway: (1) do NOT glue down carpeting or padding---use carpet tacking strips with machine stretching during the carpet installation; (2) use a digital hygrometer [$30 from Home Depot, Lowe's] to check the indoor humidity level in the basement. To discourage mold growth, humidity needs to be in the 30 to 40% range. To encourage mold growth, 60% or higher indoor humidity will make mold a permanent guest in your home; (3) use our do it yourself mold test kits to mold test your entire basement and house for mold infestation. Test the air of any attic/basement/crawl space, garage, each room, and the outward air flow from each heating/cooling duct register for the possible presence of elevated levels of airborne mold spores, in comparison to your outdoor mold control test. You should also collect samples of any visible mold for mold lab analysis and mold lab mold species identification by using the Scotch tape lift sampling technique explained on the mold test kit instructions of Mold Mart. Collect a different mold sample from each different mold growth location.

           Q. A MOLDY EXPERIENCE I WILL NEVER FORGET: We are presently looking for a new home.  We found one at least we thought we did this weekend.  The owner of the home came to show us this house.  It was his parents home and since they died he really has not visited this area.  When we arrived at the home, the owner took us through the house. He pointed out that under the kitchen sink a pipe had broke that is why the cleaning supplies were out on the floor.  We walked through the home and noticed there was a candle lit and the heat was turned up in the one bedroom and the windows were opened.  We liked what we saw and my husband decided to ask if we could see the basement.   The nightmare has begun!  MOLD was everywhere.  Big Fuzzy Mold on clothes hanging on a clothes line.  A refrigerator that looked like it was out of a horror film.  It was all over an old ironing board.  Covered drywall that must have en cased a chimney.  Parts of the insulation was hanging down from the ceiling.  It was covered all over the furniture.  It was sickening.  The owner kept re-assuring me that this could be remedied with bleach and water and that after it was cleaned, they would use waterproofing sealer on the inside walls.  The nightmare stories I hear are incredible.  This sale would be through the owner not through a realtor.  How do I know if this mold spread to the first floor?  I feel that this would not be a good venture.  Can you please tell me what kind of advice you can give to first time homeowners in regards to this Moldy situation?  [October 4, 2004]
           A. Basement mold easily grows into the insides of the walls and floors above. In addition, airborne mold spores from the basement mold will travel in air currents to mold cross contaminate the entire house and its heating/cooling system. If you buy this mold hell, expect to pay from thousands to tens of thousands of dollars to find and to remediate all of the mold problems. Learn the 25 steps required for safe and effective mold remediation at Mold Remediation. You will also need to find and fix all water problems that make the mold grow in the basement---perhaps by spending thousands of dollars to dig out the dirt all around the house to properly waterproof the outside of the basement walls and foundation. Even if you find and fix all mold and water problems, you will still probably have to disclose the mold history of the house to any prospective buyer or tenant if you decide to sell or rent the house in the future. If you are serious about buying this mold hell,  your first step is to hire a Certified Mold Inspector to thoroughly inspect and test the entire house, including the use of fiber optics inspection inside walls/floors/ceilings. Whether for this house or any other house, you would be wise to read our three in depth mold books [Mold Health Guide, $49; Mold Legal Guide, $49; and Do-It-Best-Yourself Mold Prevention, Inspection, & Remediation, $49] for just $98, the price of only two of these valuable “how to” manuals when your purchase them at Mold Mart.

            Q. Our home's basement hardwood floor moisture and mold problem was realized when planks starting popping up.  We called the people who installed it, and they said because the floor was placed on a room that is below ground level and the excessive snow that we had gotten, the excessive moisture caused the problem.  The inspector who came also had a moisture checking device that he ran over the floor.  He said the moisture level was off the charts.  My concern was that the floor company probably shouldn't have placed a glued down hardwood floor on a below level floor (which is concrete).  Does this moisture present a mold problem? Your advice and help is greatly appreciated. [March 27, 2004]
           A. The moisture problem in and under the hardwood floor is going to cause massive mold growth. Remove and discard the hardwood floor in the basement. Don't use wood [or carpeting or anything else that is cellulose-based] again there. You will need to do mold remediation of the area beneath the floor. You will also need to find and fix the water intrusion problem in your basement. If you are having moisture rise up from the concrete basement floor because of improperly sealed concrete slab [e.g., no or degraded moisture barrier beneath the concrete floor], one option is to put about an inch or two inch new concrete layer CONTAINING ADEQUATE AMOUNTS OF WATERPROOFING COMPOUND over the present basement floor. Then install a ceramic-tiled floor over the new concrete floor, and use waterproofing compound in cement holding the tiles in place and in the grout between tiles. If you have water intrusion from the basement walls, you could install an inner, new cement  wall coating one to two inches thick [containing adequate amounts of waterproofing compounds] to stop water intrusion.

Basement Mold Problems and/or Moisture Problem Questions?