5 Tips for Using a Vapor Barrier in Your Foundation

A vapor barrier is a layer of protective material laid across the foundations of a house, insulating it from the effects of moist air rising from that can carry mold and other harmful particles, as well as causing moisture damage and wood rot on the fixtures.

Tip One - Clear The Air

A lack of ventilation in an area can cause "moisture pockets" in the space; these are places where moist air has managed to get a foothold on the surfaces and can cause mold to form. To prevent these, check the area for any ventilation ducts and make sure they are clear of debris or plant life that may block air circulation.

Tip Two - Get Rid of Mold

When applying a vapor barrier to your home, the first step you should take is to clean the foundation area fully. Take a bucket and mix the laundry detergent, bleach and the warm water together. You'll be working with mold particles and bleach in a confined space, so some form of face mask and eye protection should be worn at this point. When the mixture is finished, wearing the rubber gloves, apply the mixture to the mold with the sponge and scrub until the area is clean.

Tip Three - Dry It Out

If you have access to a dehumidifier, you may need to place it within the foundation area to extract any latent moisture before continuing. Place the humidifier on a cinder block, or wooden plank for better circulation and run a hose-pipe from the vent in the machine to an outside area. Take care to ensure the hose is always aiming downwards and doesn't snake over any obstacles. Most dehumidifiers drain water via gravity, and obstacles would prevent this. You may need to leave the humidifier there for a day or two.

Tip Four - Put Down the Sheeting

Once the area is dry, apply the polyethylene sheeting to the ground, ensuring every part of it is covered. If you are using more than one sheet, make sure they overlap by at least six inches, to prevent leakage. Generally, the sheeting should rise up the walls slightly to ensure complete coverage, but not too much. Once the polyethylene is laid, take the turf staples and hammer them into the sheeting, with one staple every 8 feet or so, forming a grid of staples holding the sheeting in place, with one in each corner.

Tip Five - Total Coverage

As an additional barrier for protection, you may wish to throw down a thin layer of sand on top of the polyethylene. Not only will this help smooth out the layer of sheeting, it will also serve as an extra layer of moisture catcher, should anything escape through the polyethylene sheeting, and, as sand is dry, it will catch and hold any residual moisture in the air.