Proper crawl space encapsulation and also radon mitigation questions
Hello, I own a 1968 cape cod style home in East Stroudsburg in the Poconos, PA (region 5). It has a full basement with 7′ ceilings and concrete floor with probably little to no crushed stone underneath. At some point, there was a ditch cut out along 2 of the walls, with stone and probably a perforated pipe added, and concrete poured back except for a small channel along the block wall. This leads to a sump pit.
Adjacent to one of these 2 walls is a crawl space entrance where an addition was put in.
I am about to hire a radon mitigation contractor to mitigate an 11pciL radon level, and a spray foam contractor to encapsulate my crawl space.
I did some research and found this product which I like as a liner for the crawl space:
However, there are a lot of irregularities in the ground of the crawl space. It appears to be dirt, but is very hard, and even seems to have some patches of concrete. There’s also a perimeter drain dug along one or two of the walls in the crawl space. I intend to use this crawl space for storage, and I will also need to access it periodically when running wires and things. Also the radon mitigator may need to put a pipe into the ground here.
I want to make sure I protect the liner properly so it’s not damaged from crawling around in there and storing things. The radon mitigator suggested laying this on the ground prior to installation of the liner. Is this a good idea?
The liner I presume is only run up the wall about 6″ or so, and then covered with spray foam. We agreed on a 3″ minimum level of spray foam on the band joist and block wall of the 3 exterior walls of the crawl space. The wall adjacent to the full basement would only have a small bit of spray foam to cover the liner. The type of spray foam he will use is Lapolla 4G. Is this a good product and a sound plan?
He said it can be installed if it’s over 20F, which next Thursday will be. Is the formulation used for cold weather less effective than that used in warm weather or the same?
The other main question I have is how to handle the hatch/opening between the crawl space and the full basement. How do we finish the encapsulation under the hatch, and protect the liner in this area?
I can provide any pictures and measurements that are requested. I will have more questions regarding the radon mitigation later, but for now am mostly trying to nail down the encapsulation and only mentioned the radon mitigation for context.
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