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3 Answers

Sheathing between foil-faced polyiso and closed-cell spray polyurethane foam

I'm working on the details of an R-40 Wall in Southern Indiana, Northern Climate Zone 4. Please see the attached file.

Among many options is to use 2" of properly layered, sealed and taped FFPIC [foil-faced polyisocyanurate] exterior to the sheathing and an Advanced Framed stud cavity filled with CCSPF [closed-cell spray polyurethane foam] on the interior. The house will have 3' Overhangs, Brick Cladding, and a 1" Rain Screen.

In Energy efficiency and durability | Asked By Ted Cummings | Feb 9 15
2 Answers

Is spraying 1 1/2" of closed-cell foam to the interior of block walls an efficient form of insulation?

I have a structure located in central AR that is 8' tall block walls. The wall cavities are NOT grouted. The walls are above ground level. The interior of the walls are lathed with 1 1/2" thick strips. Im looking to spray 1 1/2" of closed cell foam directly to the blocks. Will this be an efficient form of insulation?

In Energy efficiency and durability | Asked By Zach Lacy | Feb 9 15
3 Answers

Are leaks in a structure...

Checking for leaks? is the Green's leakage decreased in homes, now that it has gone green? Or, is it basically the same / near or = to studies (in normal construction techniques)?

In Plans Review | Asked By arf shr | Feb 8 15
1 Answer

Is there any manufactured "thermal-bridge-free" door hardware on the market?

As we seek to reduce and eliminate thermal bridges in our buildings, things like door hardware show up as thermal bridge challenges. Usually, door hardware consists of assemblies of thermally conductive metal that "bridge" the door, conducting heat from the interior through the door (insulated or uninsulated) to the exterior. Thermally conductive hardware may seem insignificant in a leaky building, but it can become more significant as the building is made tighter and more thermally efficient.

In Green products and materials | Asked By Albert Russell | Feb 10 15
8 Answers

Air Exchanges in a new house

We are building our retirement home in zone 3 at the coast in North Carolina. I've come to know more about some of the design considerations for HVAC thanks to this site and I'm looking for some reassurance given that all our savings are going into this project.

In GBA Pro help | Asked By John Pugh | Feb 6 15
10 Answers

Why does my cathedral ceiling have this gable vent?

Ever since I bought my house, I have been perplexed by this gable vent. Cathedral ceiling is about 22 feet at that point and looks like behind hinged lid there is nothing but a foot deep empty space and ridge vent visible.
Was the purpose of this vent to help cool the house in summer?

In General questions | Asked By Apollo S | Feb 9 15
2 Answers

StoGuard WRB

Can one apply a product like StoGuard with EmeraldCoat WRB on OSB roof sheathing and then at a short time later apply a peel & stick membrane over it?

Will the peel & stick adhere to OSB covered with StoGuard WRB?

In Green products and materials | Asked By Peter L | Feb 10 15
15 Answers

Solar rock storage

I have a 800sft insulated cabin with a 16'×48'×2.5' rock storage, with 4"-8" rocks, and insulated (R-8) on the vertical sides and bottom with vapor/water barrier. The top surface of the rock storage is UNINSULATED and in direct contact with a 3"-4" concrete slab above with vitreous tiles on top.

In Green building techniques | Asked By Ajay Goyal | Feb 6 15
1 Answer

How to prepare a window opening in a concrete basement (foundation) wall

Obtaining Airtightness and reducing cold bridge

In Energy efficiency and durability | Asked By zoya duba | Feb 9 15
2 Answers

How risky is a single layer nailbase SIP over a single stud wall with sealed sheathing?

In the quest for a cost-effective, durable super-insulated wall, we've typically done double stud walls with dense pack cellulose, with the air barrier/vapor retarder on the inside behind the sheetrock (polyamide), and sometimes had the exterior sheathing (plywood or fiberboard, or a combination thereof) taped as the air barrier. We've also designed walls with a single stud wall and the exterior sheathing (typically OSB) sealed as the air barrier, and two layers of rigid foam sheathing to the exterior, with furring strips over the WRB over the foam, fastened through to the studs.

In Energy efficiency and durability | Asked By Rachel Wagner | Feb 9 15
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