Live in basement with moisture

[soboyle]

My parents house is a raised ranch in massachusetts, they have been having mold smells in the live in basement part of the house for years, and its getting worse. Carpet on all the floors. There is no obvious source for the moisture, so I am assuming that it is coming from the foundation. But, the area they live in is an old sand/gravel pit, the soil is very clean sand, no clay in it, that drains very well. So perhaps its a condensation problem, and not moisture weeping through the wall. My father built the house 35 years ago, and he thinks that he put rigid insulation on the inside of the foundation wall, then framed inside of that for the interior walls. I'm wondering what the proper way to insulate a live in basement like this, could we be getting moisture building up between the foundation wall and the foam, then it might run down the wall and get into the shoe of the stud wall and into the carpet?
Or perhaps a problem between the carpet and the concrete slab below it? Any thoughts on how we might figure out where the moisture is coming from?

[soboyle]

Nobody? This seems like a pretty typical problem with many houses with finished basements. Looking for best way to repair moisture/mold problems with live in basements. We intend to tear out the carpet, inspect for additional problems in stud walls, then put down a new floor. Hope to identify the moisture problem, thought it might a typical problem with finished basements.

Any recommendations on a good flooring for finished basement? Something that wont grow mold. Tile is an option, didnt know if there were some new types of flooring that looked good and would work well over a concrete slab, and aren't so cold on the feet as tile.

[Don_P]

Sorry for the slow response,
First I would check the relative humidity down there, if nothing else it will establish a benchmark. A pinless moisture meter (Wagner makes good ones) would allow you to slide around and look for high readings. A woodworker/ cabinetmaker might have one you can borrow. Look outside for missing downspouts, negative grades, that type of thing. It's also possible that warm moist summertime air is condensing on cool surfaces that are below dew point.
Its a typical problem with a variety of possible causes. A dehumidifier might tip the balance.

[soboyle]

After doing some homework, it seem likely we are getting moisture from the basement slab, capilary action drawing moisture from the ground below the slab. This in turn is causing mold problems in the carpet on the floor. I've been on the EPA site which has good recommendations for clean up of mold problems, but they make no specific product recommenations.

Are there any recommended sealers we can use on the slab that would prevent moisture moving up through the slab?
We will look into any other water problems like directing downspouts away from the house.

[Don_P]

Have you done the "duct tape a sheet of plastic to the concrete floor and look the next morning for condensation" test?

You might want to try googling on silanes or siloxanes and see if they would fill the bill.

[dlavoie]

After doing some homework, it seem likely we are getting moisture from the basement slab, capilary action drawing moisture from the ground below the slab. This in turn is causing mold problems in the carpet on the floor. I've been on the EPA site which has good recommendations for clean up of mold problems, but they make no specific product recommenations.

Are there any recommended sealers we can use on the slab that would prevent moisture moving up through the slab?
We will look into any other water problems like directing downspouts away from the house.


Have you heard of a Product called DriCore? I haven't used them, but they are moisture barrier panels that are designed for foundation floors. They include a polyethylene material that has "cleats" which raises the subfloor about 1/2" off the ground. These polyethylene sheets are bonded to the underside of the subfloor panels. So basically, you have an airspace between the foundation floor and the living area keeping the living area dry.