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3 Answers

Exterior Door Thresholds

We are building a double-stud house in Iowa -- and have a wonderful builder to work with, even though this is the first such house he has built. The problem we are having is with exterior doors. We want the doors to open to the interior, and so they are "innies". But the widest threshold we can find for an exterior door is 8 1/2". All suggested solutions are complicated and/or limit the range that the door can open. Does anyone know of a company that makes a 13" threshold?

Asked By user-6870177 | Apr 11 18
10 Answers

Furring strips and Roxul

I just applied for our building permit for a major remodel, climate zone 3 coastal, headed for a ‘very good house’. I’ll be the owner builder.

The 2x4 wall is sheathed in CDX, blueskin, 1.5” Roxul, 1x4 furring strips, cladding (stucco downstairs, banding divider, then fiber cement siding upstairs).

Asked By Phil Boutelle | Apr 3 18
8 Answers

Main Floor Cantilever

Hello. I am working on a project where the main floor is cantilevered over the concrete foundation wall. I am having a hard time finding details showing the sealnt, barriers, and insulation for the cantilevered floor. The details I do have show a cantilever over a wood frame wall, not a concrete foundation wall.

any suggestions would be greatly appreciated. Thank you.

Asked By user-7049485 | Apr 9 18
8 Answers

AdvanTech as Air barrier

Just wondering if AdvanTech sheathing could be used as an air barrier if taped?

Just wondering because of the past failures of OSB as an air barrier.

Also if so, what tape, I was planning on using 3M All Weather Flashing Tape but not sure if anyone had experience using it on this product?


Asked By Dave B | Apr 6 18
8 Answers

Does exterior foam sheathing create a second vapor barrier?

What I never quite understood is that in cold climates (I'm in Wisconsin, climate zone 6) vapor barrier is required on the warm side of the wall (under the gyp). By adding exterior foam, aren't you essentially creating a second vapor barrier which would not allow the wall to breathe or dry to one side? What's the perm rating of 1" XPS?

Asked By Bryanw511 | Apr 7 18
20 Answers

Best practices for cutting foam?

What are people doing to cut EPS foam and control the dust and debris generated, considering the toxicity of the fire retardant chemicals in it?

Some argue the fire retardants are OK, because they don't leach out of the foam much. But it seems to me that the environmental release is probably dominated by the dust and debris generated.

Asked By Charlie Sullivan | Jul 6 15
15 Answers

To Spray foam or not?

I am trying to decide whether to spray foam my house which is currently down to the studs. I am in climate zone 2 so it is hot and humid most of the year. The house currently was built to have a vented attic. The house is about 3,000 square feet and is one story. I have a asphalt roof shingles that I had installed last summer. My HVAC equipment and water heater are in a mechanical room separated from the living space by walls and with a louvered door to the outside.

Asked By Kasey Doggett | Mar 18 18
1 Answer

Recessed wood framed floor system level with frost wall?

We have an existing building with a concrete slab with interior insulated poured frost walls in zone 6A Southern Maine.
Planning an addition using again interior insulated poured frost walls at the same elevation as the existing frost walls. But in the addition we want a low height crawl space for plumbing & storage with a wood framed floor finishing out roughly the same elevation as the existing concrete slab or top of existing frost walls.
How do we connect I Joists to the inside of the poured wall?
1) create a 4" ledge in the top of the poured wall?

Asked By user-7031237 | Apr 3 18
3 Answers

Retrofit duct sealing (sealing on all sides)

I've read through the Tape vs. Mastic article and have looked at various how-to guides for duct sealing, but I feel like I'm missing something.

In our home, most of the ducts run along the basement ceiling, including some within floor joists.

It makes sense how I'd apply tape to the sides and bottom, since those are easily accessible, but how would the tops get sealed?

Asked By Timothy Tucker | Mar 21 18
12 Answers

Fiber faced polyiso

Ive got a opportunity to purchase reclaimed polyiso with the black fiber facing I plan to cut and cobble this and use it in my bonus room I will be stacking (3) 2.5 inch pieces in the catederal part of ceiling and leaving a 3.5 inch gap between the roof deck and foam as I have 11 inch rafters. for ventilation from soffit to ridge. Im in north Carolina and am required a r38 so my question is should i add another layer and reduce ventilation gap. And also which way should I face the black fiber facing. Thanks in advance for answers.

Asked By Eric Teer | Apr 1 18
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