Wall Assembly Question Zone 4A
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Hello
I am in Zone 4A in NY and am planning the following wall assembly for a single family house:
sheetrock
R21 Rockwool batt in 2×6 wall
cdx
hydrogap
cedar shingle
We are planning to use the Aero-Barrier system for air sealing prior to insulation.
Any thoughts here are welcome!
thanks!
Brad
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Replies
If a modern code is being enforced your plan is a no go. 20+5 or 15+10 in zone 4.
The last time looked Aero-Barrier pricing it seemed like the target market is contractor too lazy to make any effort at air sealing with a low price to make the local code minimum number and very expensive if you want anything better.
The question is are you interested in building better than the minimum allow by law? Will you be in the house the 15+ years it will require to recover the cost of the extra insulation.
My list of poor choices for a new home.
Half story designs.
Sloped ceiling.
Spray foam.
More than 15% of the wall area being windows.
Skylights.
Ductwork in the attic.
Recessed light fixtures
Walta
I'd do a blower door test before calling in the Aerobarrier crew. You might not need it and could put that money toward something more fun like PV on the roof.
Nothing against Aerobarrier, it looks like a great product/service and I'm sure there are occasions where it is the best solution, but if you're being conscientious about air sealing throughout the design and build it just might not be needed.