View Single Post
Old 2015-01-25, 12:52 PM
bookiej_hmbs bookiej_hmbs is offline
Junior Member
Regular User
Join Date: Jun 2013
Location: Ottawa
Posts: 28
Question Wall insulation

I'd like to hear some feedback on what to do with insulating my walls.

I've read a bunch of different methods people use, however I can't seem to settle on one. I plan to affix 1.5" rigid foam to the bare foundation walls using PL Premium or something similar, tuck taping the seams, and caulk/ sprayfoam (Great Stuff) the top and bottom edges.

If I use XPS rigid foam and the method above, I believe this will satisfy the vapour barrier requirements, based on the permeability of the foam. XPS is more expensive than EPS. R-value of 7.5 for 1.5".

If I use EPS rigid foam, I may still require a VB, there is less R-value per 1"thickness (R5.63 for 1.5"), however it is much cheaper in comparison to XPS. The EPS is also more permeable, so I believe this could be a pro, in the sense that if there is a bit of moisture, the EPS "breathes" more and can dry to the inside. This would be hindered however by a VB.

I also recently heard of Roxul ComfortBoard. It is more on the affordable side like EPS, is affixed with nails into the concrete, and it's properties are that it is vapour permeable and water resistant, allowing the wall system to "breathe". It's R-value is 6 for 1.5" thickness. There seems to be mixed information as well with regards to using a house wrap on the concrete before the comfortboard, and the use of vapour barrier or air barrier before the drywall.

I welcome any and all thoughts or personal experiences and anecdotes.
Mattamy HMBS
Oak End - Elevation B
Moved In - May 1, 2014
Reply With Quote