Application Below-Grade (Region #5a) Exterior Block Wall Insulation: Polyisocyanurate board (Yes or No)
Tony_From_Ohio
| Posted in General Questions on
It seems like this is Yes or No answer but please indulge…
Regarding what type of insulation may be used on the exterior side of a block masonry basement foundation wall (CMU) that is below-grade in a Cleveland, Ohio. (Region #5a)
What I’d like to know may the rigid-board formed using polyisocyanurate be used when installed outside? Yes it may be used or No it may not be used.
If No, what type of insulation is best on the exterior wall that is below grade?
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Replies
No, you can't use polyiso in below grade applications on the exterior due to issues with moisture wicking. Your options are EPS, XPS, and rigid mineral wool here. I've never used rigid mineral wool myself. EPS is cheaper/greener, XPS may be more easily available if you only need a little. Rigid mineral wool is the most expensive option.
Bill
Thank that is what I read but then on the Rmax site for their product called THERMASHEATH®, which says it is a closed-cell polyisocyanurate (polyiso) foam core and it's the product data sheet for THERMASHEATH® is titled BELOW-GRADE EXTERIOR WALLS APPLICATION...
https://static1.squarespace.com/static/57a39be0579fb3a3a8540f56/t/5e84a111f7732f0997bfc172/1585750289979/Rmax+Thermasheath+Application+-+Below-Grade_2020.pdf
https://usa.sika.com/dms/getdocument.get/699fa898-04d5-40d3-bfde-15eaa6684fab/Rmax-Thermasheath-Product-Data-Sheet.pdf
on the Rmax site for their product called THERMASHEATH®, which says it is a closed-cell polyisocyanurate (polyiso) foam core and it's the product data sheet for THERMASHEATH® is titled BELOW-GRADE EXTERIOR WALLS APPLICATION... https://static1.squarespace.com/static/57a39be0579fb3a3a8540f56/t/5e84a111f7732f0997bfc172/1585750289979/Rmax+Thermasheath+Application+-+Below-Grade_2020.pdf
This is my second post and I'm not sure where the first post reply post went... https://www.youtube.com/watch?v=Pexo73HeFxw&feature=youtu.be
https://usa.sika.com/dms/getdocument.get/699fa898-04d5-40d3-bfde-15eaa6684fab/Rmax-Thermasheath-Product-Data-Sheet.pdf