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Southern Ontario, Canada – Basement Insulation Detail

ChrisD_Ontario | Posted in General Questions on

I am hoping the GBA community could help me out or maybe provide some guidance/input on a material selection for an upcoming build.

I have been researching various types of insulation to be applied both under the basement slab and within the basement wall detail. I have stumbled upon a local insulation provider who has a product that has been approved for under slab insulation, see link here–>

This product seems to be approximately half the cost of the leading competitors and will provide R11.4 at a thickness of 1-3/4″ for each layer of insulation which meets our R10 insulation requirement for under the slab.

My question is, this product is only verified and approved for use under a concrete slab, could this product be used between the framed wall and foundation wall within the basement? This product is one third to half the cost of similar products on the market. Does the community see any glaring issues of why you would, or would not want to attempt this? 

I have reached out to the company, and they do not intend to expand their approvals for additional uses anytime soon. I understand that this could be done regardless of approvals if approve and signed off on by an engineer. This does not necessarily make it a good idea.

Thank you for the input. I have also attached the datasheet.


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  1. Expert Member
    Akos | | #1

    I can't see that being cheaper than regular EPS or polyiso. Nothing wrong with using it on walls, but you would still need to protect it with drywall.

    P.S. R6.5/inch is only initial R value. Most polyurathanes drop down to 5.5 to 5.8 over time.

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