hoppyending OP t1_jabfzok wrote on February 28, 2023 at 5:33 AM

Reply to comment by SnowFlakeUsername2 in Add additional insulation to walkout basement wall cavity. Good idea? Bad idea? by hoppyending

Good to know. I was concerned about it being on the wrong side of the vapour barrier.

woodprefect t1_jace031 wrote on February 28, 2023 at 12:47 PM

You don't want to use a vapour barrier at all if you will hang drywall. The moisture will move through the drywall but not the plastic and now you have mold conditions.

Keep the vapour in or out or allow it to pass all the way through.

>Incorrect use of vapor barriers is leading to an increase in moisture related problems. Vapor barriers were originally intended to prevent assemblies from getting wet. However, they often prevent assemblies from drying. Vapor barriers installed on the interior of assemblies prevent assemblies from drying inward. This can be a problem in any air-conditioned enclosure. This can be a problem in any below grade space. This can be a problem when there is also a vapor barrier on the exterior. This can be a problem where brick is installed over building paper and vapor permeable sheathing.

https://buildingscience.com/documents/digests/bsd-106-understanding-vapor-barriers

If you _have_ to use it for code use certain tweed's which allows the interior to dry.

https://www.certainteed.com/insulation/vapor-barriers/

CrispyBacon_87 t1_jack1am wrote on February 28, 2023 at 1:41 PM

This is so ass backwards.... You're contradicting the building codes of countries around the world.

Thrawn89 t1_jacss96 wrote on February 28, 2023 at 2:47 PM

You must always follow local code. They require vapor barrier on the interior side of the wall above grade. Also your links just say incorrect use will cause problems, they don't say don't use vapor barriers at all.