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Jeremiah Hein Posted: Dec 21, 2010 11:11 AM	Encapsulated Crawlspace Question First off I'm on here about every day but I don't post much. Been in the Biz 2 years. Lately we've been getting calls for doing Encapsulated Crawlspaces. What we've been doing is a 10 mil polyethylene on the dirt combined with a closed cell on the walls creating the conditioned crawlspace. Excellent article in the newest JLC Magazine on using mastic btw. This is what I've come up with we bring the liner up the wall 6 inches or so and at the point use either the mastic or vapor tape to seal it to the wall. Then we spray the closed cell down over top the joint and overlap. Finally my question. What is going to be the long term effect of this system. The closed cell is overlapping and pinning it down but not adhering to the liner. Will moisture migrate thru that joint eventually?
jimcoler I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs. I've expanded my knowledge into t Posted: Dec 21, 2010 09:53 PM	We've been using something similar but it's also an insulation barrier for the floor. It's called Low-E insulation and can be easily put down on the dirt floor and comes with double stick tape on one side for easy install. This provides an R-8-11 insulation value, a vapor barrier and a radon retarder if installed properly. It comes in 4' and 6' wide rolls and is great to use for crawlspaces. We'll bring this up the walls about 6" or so and foam it in along the walls for a tight seal. In many cases we even use open cell foam because it is still an air barrier and still provides the thermal control. It's also cheaper than closed cell and remains more flexible! Jim Coler

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Jeremiah Hein

Posted: Dec 21, 2010 11:11 AM

Encapsulated Crawlspace Question

First off I'm on here about every day but I don't post much. Been in the Biz 2 years.
Lately we've been getting calls for doing Encapsulated Crawlspaces. What we've been doing is a 10 mil polyethylene on the dirt combined with a closed cell on the walls creating the conditioned crawlspace. Excellent article in the newest JLC Magazine on using mastic btw.

This is what I've come up with we bring the liner up the wall 6 inches or so and at the point use either the mastic or vapor tape to seal it to the wall. Then we spray the closed cell down over top the joint and overlap.

Finally my question.

What is going to be the long term effect of this system. The closed cell is overlapping and pinning it down but not adhering to the liner. Will moisture migrate thru that joint eventually?

jimcoler

I have over 10 years of experience specifying and installing open and closed cell spray foam. I've sold my business but I'm still selling for the new owners and consulting on large and custom specific jobs.

I've expanded my knowledge into t

Posted: Dec 21, 2010 09:53 PM

We've been using something similar but it's also an insulation barrier for the floor. It's called Low-E insulation and can be easily put down on the dirt floor and comes with double stick tape on one side for easy install. This provides an R-8-11 insulation value, a vapor barrier and a radon retarder if installed properly. It comes in 4' and 6' wide rolls and is great to use for crawlspaces. We'll bring this up the walls about 6" or so and foam it in along the walls for a tight seal. In many cases we even use open cell foam because it is still an air barrier and still provides the thermal control. It's also cheaper than closed cell and remains more flexible!

Jim Coler

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