How To Install Vapor Barrier On Concrete Walls

A vapor barrier is not the same as an underlayment.

How to install vapor barrier on concrete walls.

The science of moisture movement. Vapor barriers are a way to keep moisture from getting into the concrete. To clean the wall mix up a dilution of water and trisodium phosphate or tsp in a bucket. Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets.

Also be sure to use treated lumber for the bottom plate on the wall framing. Thus installing vapor barriers on wall surfaces must. This is why a vapor barrier under concrete is essential. Follow the instructions on the tsp when measuring ratios of water to tsp.

This barrier is meant to keep moisture from getting to the insulation in the walls and ceilings and it is required by building codes when insulating most houses. To be extra certain use a caulk gun to place caulk material around the tape to double seal the barrier. In any case the vapor barrier must point to the warm side. The problem is that moisture tends to condense on the cool concrete walls.

In this video you ll learn how to install a proper poly moisture vapor barrier against your block basement wall before finishing and closing up your wall sec. The water vapor can come through the concrete from the soil or from indoor air that comes in contact with the concrete. If you have a concrete floor that s in continuous contact with a source of moisture you re going to have problems. Of rigid moisture proof insulation.

Using other kinds of tape will compromise the waterproof seal and render the barrier useless. To be effective a vapor barrier must be installed in a way that prevents any water vapor from getting to the slab. With fiber insulation and a vapor barrier moisture can get trapped in the insulation leading to moldy insulation and decay in the wood framing. We used thermax brand available through lumberyards of polyethylene vapor barrier because it doesn t require an additional fire barrier.

Find out where to buy vapor barriers and other problem solving products. Finish the wall within a month of installing the barrier to prevent damage to the surface and protect the vapor barrier. Cover exposed foundation walls with 1 1 2 in. This not only insulates the walls but also keeps rising dampness in the concrete from getting into the crawlspace.

Before attaching the vapor barrier to the wall it is essential that you wash the concrete to remove substances such as mold grease or sand.