Vapor Barrier is a plastic installed in order to protect an area from the earth's moisture and humidity. Such moisture can lead to contaminated insulation, which affect the quality of air you breath. Vapor Barriers also provide protection from harmful gasses coming from underground. We offer 6 mil or 14 mil vapor barriers, respectively to our customer's requirements.
Crawlspace vapor barriers, are one of the most commonly installed type of barrier. Today in the Pacific Northwest, black 6mil polyethylene plastic sheeting is the most commonly required vapor barrier for crawlspaces. Many older homes with have improperly installed vapor barriers or older, white/clear ones that do not provide the full benefits as expected by today's standards.
A crawlspace vapor barrier prevents ground moisture from rising and impacting the crawlspace area. A vapor barrier should fully cover any exposed ground dirt up to any concrete or foundation walls. It should not, however, touch any wood such as foundation posts. Any such contact would expose wood to the moisture below that the vapor barrier is intended to block. This could lead to mold issues or even worse, harm the structural integrity of the building.