Moisture on my pole barn concrete floor
Inside my pole barn the concrete floor always feels damp. When we poured the floor years ago poured it over gravel. Someone said to me that I should have put a vapor barrier down like a sheet of plastic then poured over top of that. Well it’s too late and I am in the process of making a little office inside my building and I don’t want to have moisture issues in that room. What are some of my options? Thank you Anthony
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Anthony,
There are three ways that you can address this issue. The first and most important step is to add a vapor barrier (polyethylene) and insulation (a continuous horizontal layer of rigid foam) on top of the existing concrete slab. These layers are usually topped by a subfloor (for example, plywood) fastened through the foam to the slab with TapCon fasteners. Once your subfloor is installed, you can install any kind of finish floor you like.
The second way to minimize moisture accumulation on your slab is to condition the air inside the space (your little office). Keeping it warm in winter, and air conditioned in summer, will help.
The third measure you can take is to examine the exterior perimeter of your building for moisture problems. Typical problems include high grade, grade that doesn't slope away from the building, or wet spots due to roof runoff. Correcting these problems will help.
Even though you are talking about a pole barn, not a basement, you may want to read this article: Fixing a Wet Basement. Pay attention to the sections that begin "Check your roof gutters," as well as "Adjust the grade around the outside of your house."
You probably also want to read the section that begins "Insulating an existing basement slab."
There are epoxies that will vapor seal the slab with surface treatments.
http://www.concretenetwork.com/products-concrete-coatings/epoxy-moisture-control.html