Today I wanted to give a quick overview of installing a vapor barrier. Here We have a roll of six mils clear reinforced 12 by 100. I like 12 by 100 the most when doing vapor barrier because of the way it unfolds. Most people When you do vapor barrier, you want to start at one end of the home. If there’s no obstruction or any pipes, and you have clearance, you can take this and unroll it down to the other end of the house and then trim it off. The reason why like 12 mil, it’s easier to work with is that It unfolds Twice.

Should I Go Up The Walls

When installing a vapor barrier, you can do it a couple of ways. Some people want to do end-to-end to the pier to cover the entire area of the crawl space. Some people like to go up the walls. When you’re going up the wall, you want to leave a six-inch or about a block clearance for a termite inspection. If you’re doing an encapsulation and laying 12 mil on the ground, you want to use a six mil clear wall liner for the same purpose.

Crawl Space Contractors
King County Crawl Space
Kitsap County Crawl Space

When installing it on the wall, a lot of people use butyl tape. This is a double-sided rubber sticky tape That you literally can install on the brick or the block. This is terrific stuff. Initially, contractors used butyl tape for roofing, and then people started using it in the crawl space. I do advise when you’re doing it, pick your area and unroll it as you go. And then take the other side. Also, once you have that installed on the wall, you can take your wall liner or your six mil clear, and that way, you can get it attached.

There May Be A Difference In Grade

The reason why you also want to do a wall liner is a lot of the time, the grade outside the home is higher than the grade inside the crawl space. When it rains, you see a lot of water seeping in. So if you have your wall liner attached to your six mil or your 12 mil, it’s going to prevent that water from getting on top of the vapor barrier. If you have that issue, if you have a constant water issue, part of it may be because of the grade inside and outside the crawl space.

Once you have this done, you want to take it to the extra step. You can use Christmas tree stakes. With a drill or a hammer drill with a quarter-inch masonry bit. I prefer Bosch bits. The tips last a lot longer than any bit I’ve ever used. You can drill in, and then you would tap this Christmas tree stake in with a rubber mallet. You want to do this every three feet or so. And that gives an excellent install.

Achieve An Excellent Seal

Down here, once you got your wall liner up over again, your 12 mil or your six mil clear, if you want to do an excellent seal. If you’re doing an encapsulation, you can use Poly tape. This is a PVC tape designed for the crawl spaces. You never want to use duct tape. Over time It’s going to deteriorate. You want to spend the extra money on the PVC tape. All you do is once you’ve got everything done, you’ll go along and tape up the seams. You always want to start and unroll.

When you’re installing a vapor barrier, you want to have a few tools. I like a pair of Fisker scissors or utility knives. Some people like to use carpet knives. A rubber mallet if you’re doing the wall liner and the Christmas tree stakes. Some people want to use a Hilti gun for this. Instead of drilling, you can also use a Hilti gun and put the Christmas tree stakes in or use a Hilti gun with the adapter they make for it.