Plastic Sheet Over Insulation In Crawlspace

At 50 to 70 cents per square foot sheet plastic is a cost effective barrier for moisture in your crawl space.

Plastic sheet over insulation in crawlspace.

Without such a barrier condensation can infiltrate your home s walls and insulation creating a substantial risk of mold and mildew. Finally cover the entire area under the house with a layer of 6 mil plastic sheeting. Up the wall and fasten it there. Purchase plastic in dimensions that limit the number of seams between plastic sheets.

However those savings may likely be lost in the long run if someone walks or crawls on the poly causing micro holes in the vapor barrier. Cut the sheets to size allowing 12 inches or more along walls. Six mil polyethylene plastic comes in rolls of various dimensions. If water vapor diffuses or infiltrates into the wall cavity and finds the cool surface moisture problems can occur.

Cover the dirt crawlspace with a plastic moisture polyethylene vapor barrier. Overlap the sheets a foot or so cut the plastic around piers and run the plastic all the way to the foundation walls. Reinforced polyethylene plastic sheeting poly comes in a variety of thicknesses and strengths. Essentially a large plastic sheet placed over the base of a crawl space vapor barriers are intended to fully cover any exposed dirt.

Unroll the first row of polyethylene in the crawlspace next to your longest foundation wall and cut it to the length of the wall. And bring the plastic about 6 in. The humid air is indoors. Plastic on the outer surface of a wall in cold weather could cause problems.

Overlap the seams by no less than 12 inches and secure them together with the poly pvc tape. Overlap any seams and tape them. If your crawl space isn t ventilated insulate the walls of the crawl space rather than the subfloor of the room above. Apply a length of double sided bonding tape 3 inches below the top.

Install the plastic sheeting only after the. Beginning at one side of the crawl space lay down 6 mil or thicker polyethylene plastic over the entire crawl space. Homeowners use plastic to cover their crawl spaces to control moisture and create a barrier against vapor. While this doesn t completely eliminate moisture it does slow the process significantly.

A 6 mil thick poly is commonly used as a vapor barrier and offers short term savings to the homeowner. Stake the plastic down with landscape fabric stakes to keep it in place. You may also want to install a polyurethane vapor barrier over the dirt floor for further protection. This requires less insulation and will eliminate the need to insulate ducts and pipes separately.