Covering up exposed foundation with siding/insulation
It’s been a little while since my last post. Shortly I’ll be starting construction of a new home in zone 6 in Ottawa, Ontario. 2 storey home with garage in the basement. I will definitely have a few more questions in the coming weeks/months.
I’m contemplating insulation options for the basement. One cost effective approach it would seem to be to use 3″ of recycled XPS on the exterior of the concrete. This can be had for well under $1 sqft in our area. I would then finish the interior with some more eps or polyiso, a VB if required by the inspector, and strapping/drywall.
My top of foundation will be about 4.5 feet above grade with my sheathing hanging just proud of the concrete wall. Self-adhered WRB/airbarrier on the sheathing, followed by 2″ of comfortboard, strapping and cement board plank siding as the main wall assembly. My question is if I can run my WRB about 3′ down onto the concrete and continue with the comfortboard/cement board until I’m about 18″ above grade to cover up the exposed foundation. I would then have my drip edge at the bottom of the siding with the recycled XPS below and finished in one of the accepted ways. I haven’t been able to find much information on doing a transition like this from wood to concrete.
Any thoughts would be much appreciated!
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