Using the excellent advice I received from this group I was able to add additional structural support to my basement’s wood floor. While in the crawl space under the basement I used some extra plastic which was under there to cover the rocky drainage leading to the sump pump and covered the plastic with dirt from my new concrete footings. That was six months ago.
Today I was under there and noticed a fuzzy white mold growing next to the plastic. The dirt on the plastic was dry and clear, but everything else was quite wet. The builder installed a ventilation fan and dehumidifier for the area. Both run constantly. A past article in FHB described the process of sealing the area with a waterproof covering, but the builder says there are drawbacks to trapping the moisture under the plastic. I would have to cover over 800′.
Should I cover it? Should I just kill the mold? If so, how? I live in Denver where it is dry everywhere except under my house.
Thanks!!!
Rich
Replies
I live in Denver where it is dry everywhere except under my house.
My question would then be..."Where is all that moisture coming from?"
If you can find the source and abate it, then the whole crawlspace might be better off and much drier.
Time for some sleuthing! Check for water and sewer leaks, dryer vents into cawlspace, rainwater leaks, drainage from exterior sources, subsurface water tables/springs.
..............Iron Helix
I live on a fairly steep hill and back to open space. While much of the surface water and snow melt runs down the street, my house appears to be on part of the natural underground drainage to the small creek in the open space. There are about a dozen other houses in my neighborhood that have similar situations.
Does that help?
Rich
Is your back yard swaled to allow the melt to move around the house rather than through it? Gotta picture?
A microscope might allow you to discern whether your fuzzies are crystaline or organic!
.................Iron Helix
The "mold" is probably salt. Water rising through the soil evaporates, leaving a salt deposit.
>"Should I cover it? Should I just kill the mold?"
Unless the underlying (water) problem is resolved, the mold will be hard to kill and will return anyway. I'm not sure what all the problems would be with covering the dirt w/ thick plastic, but I do know that it stops mold (or at least contains it) effectively. One thing you mightg consider, though, is the change in the relative humidity caused by sealing off the wet dirt. If the floorboards above were installed tightly, you can expect a noticeable expansion of the cracks in between as the boards permanently shrink.