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3 Answers

Question about building envelope/insulation around garage and walls bordering garage

As you may recall, we put 2 layers of foam (7" XPS and 2.5" EPS) above our 1:12 roofline so the attic is conditioned space. The exterior of our house will have 2" rigid foam and EIFS. Exterior 2x6 wall cavities will be filled with blown-in cellulose.

In Green building techniques | Asked By Kevin Hoene | Dec 21 15
2 Answers

Help with re-flashing leaking windows

First off, these are outies installed in a 2x6 wall with 4" of xps on the exterior.

In General questions | Asked By Mike | Dec 21 15
6 Answers

Proper insulation installation


In Energy efficiency and durability | Asked By Greg | Dec 21 15
10 Answers

Neutral pressure plane?

Background, my house has about 15ACH50, much of it coming from a very shallow crawlspace i cannot access (never mind fix, i hope to dig it out enough to access the entire perimeter of the house and encapsulate it someday)

In Energy efficiency and durability | Asked By Alan B | Dec 18 15
5 Answers

Economical but effective airtight and vapor-impermeable sealant for OSB?

I'm in northern CZ-4- Mixed Humid. I plan to have a 2x6 advanced framed wall with OSB on the outside and unfaced fiberglass batt cavity insulation. There will also be a layer of Continuous External Insulation, a 1" Rain Screen and Brick Cladding. The type of CEI is as yet undetermined.
I want the assembly to be Vapor Impermeable to the potential vapor drive from wet brick and Air-Tight. The OSB would dry to the interior.
My question pertains to a possible coating for use on the OSB to accomplish this.

In Energy efficiency and durability | Asked By Ted | Dec 20 15
10 Answers

Plywood boxes for window openings in double-stud walls

Builder didn't allow for plywood boxes in the window and door openings of the first 3 walls of our double-stud house project (zone 5 SW MI). Anything we can do short of tearing them out and re-doing them? We'll be using drywall returns. Does the box serve any purpose other than connecting the two walls? Can we net and dense-pack like everywhere else and just not use the boxes?

In GBA Pro help | Asked By Dave Owens | Dec 18 15
5 Answers

Best insulation for the ceiling in an attached basement garage?

My dad and I both have the same problem: not enough insulation in our attached basement garages. I at least have the advantage of living in CT (Zone 5) and having some poorly sealed drywall and some fiberglass insulation on the garage ceiling. The floors are a little cold, but it could be worse. He owns a log home in northern VT (Zone 6) and has zero insulation on the garage ceiling, which makes his living room floor more than a bit chilly.

In Energy efficiency and durability | Asked By Amanda | Dec 19 15
1 Answer

Closed-cell vs. open-cell spray foam and exterior rigid foam on the roof

In climate zone 5 if you use a roof wrap, rigid insulation and a vented area under a metal roof on top of the roof sheathing, then is open cell foam better for the underside of the sheathing since it would allow the roof sheathing to dry out - OR - would a closed cell foam or other vapor barrier still be needed? Thanks.

In Energy efficiency and durability | Asked By Michael | Dec 20 15
2 Answers

LED shower lights?

My electrician is recommending recessed shower lights for two bathrooms that are below an un-conditioned attic in a new addition. Can you help me find LED surface lighting that can tolerate the moisture of the showers?



In Energy efficiency and durability | Asked By David Martin | Dec 20 15
18 Answers

Can a foundation drain to daylight double as a radon vent?

Ok this is probably a dumb question, but I'm looking at putting in an addition this spring, and was looking at ways of draining it and stumbled onto radon mitigation. So now I'm not sure how it would all fit together.

In GBA Pro help | Asked By Terry Sharpe | Dec 15 15
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