Insulating and envelope in East Ontario
Hi, Thanks for all the writing and information. I’ve been digesting as much as I can. I am not a builder, so much of the technical details on implementation vs theory are likely missed by me. As in what works and is deployed in my geography.
I am planning a single family, slab on grade, 4 bedroom, 2900sq ft home near Ottawa, ON (DOE zone 6A, almost into 7 I think.) There will be a loft above the garage. South facing house for the most part.
I have a few ideas from builders. One ICF builder with radiant floors and forced air AC, One Stick frame with exterior foam and Batts (looking into BIBs) and forced air furnace (96% efficiency) and AC.
My current thought is 3″ exterior foam (R 12), BIBs (R-23) for an R 35 wall. The builder does 2×6 16″o.c.
As for the Slab. I want lots of insulation. We can source reclaimed EPS, 4″ I think for underslab (R-16). I looked at insulation rafts (legalett), FPSF, and frost wall. Not sure I can get these built.
Attic floor: Thinking 2″ Closed cell (R12) to air seal and blown in on top to R 70. Would foam board work instead of spray foam. Thinking 1.5″ foam board taped with drywall over it. Thoughts?
The ICF builder uses Nudura block and underslab insulation. I think I can get more bang for my buck doing Stick and forced air with the first builder.
I am trying to grasp windows right now. I think the idea is high solar gain on the South facing and cheaper on the North.
Any thoughts on this approach? I hope to use beOpt software to model and get a Manual J too. But this stuff is still a little beyond my knowledge still.
Also, just getting into the details about where HVAC ducts go. Like Plenum trusses or soffit. The ICF builder says he does a drop ceiling (9′ ceiling interior but a 1’cavity above that for ducts. I think the stick frame builder could do the same, but it’s more sq ft to build so more money.
Lots to go through. Struggling with many aspects and just trying to get some thoughts and ideas. Appreciate our time and insights.
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