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1 Answer

Air transfer through soffits

Hi Martin....I am building in zone 5 and have chosen to spray the roof deck with closed foam backed with open cel. There will be no air coming in through the soffits since the foam fills the roof joist cavity above the plate on the outside walls. My question is regarding the roof joist tails beyond the exterior walls. My intention was to close those soffits with cedar without any venting considering there will be no way for air to get out if I allowed it to get in. Is this an acceptable practice?

In General questions | Asked By Consor Development ternes | May 18 17
2 Answers

I provided my Visa card info to start a one month membership but can't log in!

New member. Having trouble logging in. Please email solution: aamchan@aol.com. thanks

In General questions | Asked By user-6848597 | May 18 17
9 Answers

Wall and roof construction ideas

We're hoping to build a house this summer. It's the first time we've done a ground-up build, though we've remodeled and lived in a couple century-old homes. I'm looking forward to building a tight, efficient house, and to no longer heating with coal. I'd like to run my proposed assemblies, along with a few questions, by the experts here.

We're building in Northeast PA, Climate Zone 5. I'm including an image of the house we're planning to build. House is about 2700 sq. ft., and if we can button it up tight enough, I'd like to heat/cool with minisplit units.

BASEMENT

In Energy efficiency and durability | Asked By Foeller32 | May 11 17
8 Answers

Exterior wall insulation

Im looking for opinions on which method would be best for my area (4). Since I don't want to build 12" double exterior walls, I'm planning to use 2X6 with packed cellulose and either 2" of styrofoam exterior sheeting or zip sheeting with rock wool exterior insulation over that. Also I think I want to use rigid foam vents furring the rafters down and packing cellulose to an acceptable r factor for a conditioned attic.

In General questions | Asked By Ralph Foll | May 16 17
2 Answers

Uninsulated cottage floor cupping

Clients cottage located in rural Nova Scotia. Built on posts. Floor not insulated. Building not heated when not occupied (most of the time) We installed solid birch flooring, and sanded and clear coated as a finished surface.

Client had asked about the need for vapour barrier between subfloor and flooring. Based on my research at the time, it seemed like this was not necessary.

Now, however, the floor is showing signs of cupping. :(

In General questions | Asked By Nick Rudnicki | May 18 17
6 Answers

Ceiling air barrier with suspended ceiling?

I'm designing a 1-story, wood frame building w/raised heel, wood roof trusses, slab on grade, in zone 5. Does this ceiling system work?

Attic insulation is R-38 kraft-faced fiberglass batt, extending over the exterior walls, with kraft facing down. (vapor retarder)
5/8" GWB ceiling as air barrier applied to bottom chord of trusses. (also supports batts.)
12"-18" high plenum space so all HVAC ducts can be inside thermal envelope and accessible. (The HVAC system will go in a mechanical closet on the slab.)
Suspended acoustic ceiling tile.

In General questions | Asked By Laura R | May 18 17
4 Answers

Foundation question: Slab on grade or monolithic?

I am going to build a small 12 x 16 Timber Frame house in the Intermountain West - Zone 6. I attached a rendering. One question I have is about the foundation. I think I am confused about the terminology that I hear. Would it be preferable to do a monolithic slab or a slab on grade with a stem wall? I know there are lots of details here and in Lstiburek's Building for Cold Climates but I'm wondering what a pro might recommend (no basement or crawl space).

In Green building techniques | Asked By John Brown | May 17 17
13 Answers

R-24 spray foam enough?

Hi there,

In Energy efficiency and durability | Asked By User-6848033 | May 18 17
4 Answers

Advice on Slicker Max rainscreen?

I am looking at a wall comprised of 2x6" frame, cellulose in the cavities, Huber Zip system exterior, 1.5" Poly, Slicker Max Rainscreen 10M, and then nailing cedar shingles directly through rainscreen and foam (approx 1 3/4").

My Builder does not want to deal with putting up 1x4" nailers every 5" to hang shingles from, so thinking rain screen will give shingles ability to breath. Depending on cost this might be an alternative.

Also not sure if this will meet code on Cape Cod with wind code, or if hanging shingles in this manner would work. Thanks.

In General questions | Asked By Steve Kreisher | May 18 17
18 Answers

Protecting Redwood siding

I have moved into a house with unpainted vertical channel-rustic redwood siding. Unfortunately, some of the siding extends down to within a few inches of the ground. In spite of there being a 2-foot gravel perimeter around the house, and in spite of there being a 2-1/2 foot eave overhang, rain splashes against the lower portion of the siding, and after 35 years it is showing signs of decay.

In General questions | Asked By Jack Woolfe | May 15 17
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