Deep energy retrofit
I’m in St. John’s, Newfoundland and Labrador, climate zone 6, about 4800 he’d, wind driven rain category is Extreme. House is 25 years old and wall structure is from inside to outside
1. 1/2″ gyproc
2. Super 6 mil poly, acoustic sealant
3. 2×[email protected]″oc studs, r20 fibreglass baths
4. T&g board something
6. Vinyl siding
Electric baseboard heat, HRV ducted to every room, r32 cellulose in a vented attic.
Without any tear up, I will upgrade the attic insulation, and at the same time do air sealing. Some of the HRV ducts run through there, and ideally I’d like to move those, but I may have to settle for just ensuring they are well insulated. These are currently the flexible insulated ducts. Any suggestions on how I may improve those ducts without moving them into soffits in the rooms below?
I’d also like to do something for the above grade walls. The vinyl siding will be reused, so I don’t need or desire a rainscreen. There is an island manufacturer of EPS, so I can get type 1 or type 2 in a slotted version 9f whatever thicknes I want. If I go this route, there will be a layer of tyvek on the t&g board. Should I also put another layer over the EPS? Should I use type 1 or type 2? I am thinking the thickness will be 2-3″, so r8 to r12.
I am also considering 2 layers of 1 1/4″ r5 Rockwood comfortboard instead of the EPS. At 2 1/2″ total thickness, I won’t need strapping. Should i put another layer of tyvek over the comfortboard? I know this won’t be easy.
My windows stay where they are so they become innies and I need to deal with that.
I am also adding a mini split heat pump.
Thanks for any suggestions.
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