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Old 01-22-2010, 11:11 AM   #1
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post-flood mold on walls: need to replace?

Our basement got flooded over Xmas. This is the second time it happens, the first time it was a couple of years ago. When I removed all the furniture from one of the rooms, I discovered nasty mold on the walls (see picture). My question is what to do at this point. We will be definitely removing the carpeting from the floor, but how do I get rid of the mold on the walls? Do I need to replace the drywall? Or can I spray some chemical on the wall to kill off the mold and then apply a fresh coat of paint? I am actually less concerned about the looks and more about potential mold allergies.
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Old 01-22-2010, 11:41 AM   #2
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Many will tell you to get an professional for "toxic mold" remediation. Some will tell you to have it tested. My opinion is you would just clean it well with bleach and water (a bit of dish soap can help too). Never mix bleach with anything containing ammonia.

All of this assumes the moisture is gone. Mold needs moisture, the correct temperature and something to feed on. Eliminate the moisture and the mold wont grow.

The bad thing is you may also have mold on the INSIDE of the wall. It will eventually die if you keep things dry but the spores can remain. If you have issues with allergies then removal of the drywall and cleaning of the wood framing might be warranted.

Me - i would eliminate the moisture, clean the mold off, repair any gouges in the drywall, replace any sections of soggy or deteriorated drywall, prime and paint.


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Old 01-22-2010, 11:51 AM   #3
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Based on personal experience investigating mold damage to buildings after floods, I would not waste the time trying to clean mold off drywall, I would simply replace it. Doesn't take any longer, and mold typically changes the texture of drywall and makes it almost impossible to match paint with existing paint on unaffected areas.
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Old 01-22-2010, 02:57 PM   #4
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I agree with DH.Get rid of this drywall then clean inside the wall.It looks like your only needing two sheets of rock.
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Old 01-22-2010, 03:01 PM   #5
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Replace the board. Definitely.
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Old 01-22-2010, 03:17 PM   #6
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In fact replace all the boards 4 feet up for the entire flooded area.
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Old 01-22-2010, 03:34 PM   #7
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Speaking from experience, as a result of flooding in my area in 1994 and 1996. I went to the classes the "Government Experts" put on in my area as to how to handle this and then worked on numerous homes. As has been stated: Do spray the areas affected with a mixture of bleach, water, and a few drops of Dawn detergent. The detergent acts as a "surfactant" to help hold the bleach/water mix onto the wall. Google the correct mixture. Do remove all affected drywall, up to four feet (4 ft.) is good. Do remove any insulation that got wet also. Place everything removed into two (2) Large Industrial Grade garbage bags (one inside the other), available at Lowe's/HD. Do allow the wooden framing to dry thoroughly. A moisture content meter is good here, but if you don't have one, allow the wood to dry as long as possible. IF you have, or can borrow, a de-humidifier is a great help in this task. A de-humidifier will help dry out the wood sooner. Actually, one instructor suggested that all surfaces which had been wet, and were hidden, behind drywall etc., be primed and preferably sprayed heavily, before covering again. Flood remediation is not fun, it stinks-literally! Even with just hard rain bringing sudden localized flood waters, this rise in water brings everything in the world out of the ground- -that stinks! Ours were cases of long, hard rains, causing a local river to overflow it's boundaries. This brought out waste from public sewerage treatment centers upstream from us- -that stinks! Good Luck, David
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Old 01-22-2010, 05:09 PM   #8
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Just get the drywall off and kill attack the spores stuck to the wood framing unless it was severely moisture damage.

If this has happened twice in two years though? Do you need to add a sump pump or perimeter system? Do you have one but the power failed? Might want to add a power backup of some kind. What's causing the floods?
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Old 01-24-2010, 10:41 AM   #9
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mold on walls

I agree the walls should be replaced, however, for the unseen mold spores that might still be lurking, you may want to check out the remarkable research on toxic mold removal done by environmental expert Dr Ed Close. Simply diffusing a therapeutic-grade essential oil regularly will likely result in an environment very hostile to mold. It seems like it would make traditional remediation projects easier and more effective, as well as creating a healthier environment in which to live.
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Old 01-26-2010, 07:24 AM   #10
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Unless drywall is completely and thoroughly dried out within 72 hours, you might as well remove it and throw it away. Not only will you never remove all the mold from it, it has been structurally damaged. At 72 hours, mold spores will mature into full fledged mold colonies and sink "roots" into the surface that cannot be removed. Cut and remove 12 inches past the water damage line. Moisture will wick into drywall almost that far from the water source. Use a 10% bleach solution to clean up the wall framing and then seal it kilz or Zinnser. Then replace the drywall. Sounds like you need to use Densarmor drywall instead of paper faced.
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Old 01-26-2010, 07:36 AM   #11
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- Rip out the sheetrock & Insulation 4' to 5' up.
- Dry area out - including framing.
- Treat area with the proper mildewcide agents.
- Replace sheetrock.

- As M6 stated = use a mold & mildew resistant sheetrock to replace.
- Also, consider sealing all wood studs using a sealing, oil based agent like Kilz or Binz.
- Replace insulation in the areas with a closed cell ridgid insulation foam board.


- Build Well -
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