Flash + Batt with Closed cell + Cellulose?
I live in New England (Zone 5) and I want to make the proper decisions while renovating my new home.
Early 1960s Ranch w/ unfinished basement.
It is very dated, but its perfect for my fiance and I. It truly feels like its the “Forever Home,” and I want to make it perfect inside and out. It already has everything you’d want in a house.
On the main floor, I plan on replacing all drywall on the exterior wall and want to upgrade / install the insulation. I want to “Flash and Batt” with a 1″ or 2″ closed cell spray foam (unsure if they are 2×4 or 2×6 yet), and some other insulation.
In the basement, I plan on finishing with 1″ R-5 rigid poly board between the concrete foundation and 2×4 / 16″ on center stud wall, and some other insulation.
My question is, can you use the “Flash and Batt” technique with closed cell foam / rigid poly board and cellulose? I can’t find any articles or YouTube video or anything about this installation technique. Is there a reason why, or is it just that no one has used this technique yet?
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Replies
Bob, there have been many articles and Q+As here about flash-and-batt and flash-and-fill assemblies. There is little difference between using batts and dense-packed fibrous insulation such as cellulose. But in walls there is usually little to no benefit over just filling the cavity with the fibrous insulation. https://www.greenbuildingadvisor.com/article/flash-and-batt-insulation