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3 Answers

Duct Insulation R Value in a Attic with a spray foam roof deck.

Definition of Conditioned Space - Spray foamed attic/roof deck
I am consulting on a new construction house for efficiency. We are spray foaming the entire house including the bottom of the roof deck. The HVAC installer finished his rough in. His duct work is wrapped with R6 insulation in the attic because he understood it was a "conditioned space"
The building inspector failed his rough in because he said the area was not directly conditioned with its own supply and return so the duct need to be R8.

What is your opinion and suggestions?

In Building Code Questions | Asked By Paul Pankey III | May 9 12
4 Answers

Wood gasification boilers

I have a friend in town who is thinking of installing a wood gasification boiler to run his hydronic heating system and domestic hot water. As I haven't come across many of these before I am hoping some of you guys can give some advice that I can pass on. I believe he is considering one of the following units; Econoburn, Empyre Elite or a Woodgun.
Many thanks

In General questions | Asked By Ray Smith | Apr 3 12
7 Answers

Zone 5 - Vapor Retarder on ceiling of indoor swimming pool

I an an insulator and a little confused on the subject of vapor retarders for ceilings. Normally we do not put a vapor retarder on the ceiling for Zone 5. But we are doing a job for someone that is enclosing their swimming pool and I am concerned that with that much humidity it might be necessary. They are installing an air-exchange unit of some kind but I do not have any details on that at this time. If this question has already been answered, can you please direct me to that thread?

Thank you

In GBA Pro help | Asked By Lisa Goodman | Feb 6 12
6 Answers

Experience with "Drain Plane"?

Has anyone had experience with Drain Plane, a recycled-plastic, vertically-applied furring strip by G.B. Williams that is sold for use in rain screen assemblies? (http://www.drain-plane.com) I wonder if it could be used over foam sheathing in place of 1x4s. Any comments welcome.

In Green products and materials | Asked By Gordon Taylor | May 9 12
32 Answers

A blog for "air-tight" sheathing nuts

For those who are interested, here is a link to a blog that I have started about my building project.

Please note that the blog has only just gotten started and has a ways to go before it catches up to the actual project.

It generally covers the technical aspects of the build but I have also included (and will be adding) construction details for a "truss wall" with "air-tight" sheathing approach I have been working on.

In Green building techniques | Asked By Lucas Durand - 7A | Dec 7 11
3 Answers

Exterior foam installation details

Our house is 2x6 construction built in 1984 near Milwaukee, WI. Going from the inside out, drywall, vapor barrier, fiberglass insulation, EPS foam sheathing, and Cedar board and batten siding.

In Green building techniques | Asked By Kacey Zach | May 9 12
3 Answers

Which exterior sheathing is better?

Which exterior sheathing system would you recommend - Zip system with housewrap vs plywood with 3M 8067 tape and housewrap? The difference in cost is only $300. We are in Zone 5a, upstate NY. We are concerned about the long term life of the sheathing and what would happen if it gets wet (mold).

In Green building techniques | Asked By Elizabeth Kormos | May 9 12
1 Answer

How do I improve R Value and change to metal on my roof?

I have an older Pan-Abode home that has cathderal ceilings with minimal roof R Value. I would like to increase the R Value and lay metal roof over shingles. Does anyone have insight on the best way to do this?

In General questions | Asked By Laurence Bishop | May 8 12
1 Answer

Zip or Rigid Foam or Both (& HVAC)

Hello - we are building in Cincinnati (4800 sq ft). Our builder is a fiberglass batt person with no exposure to any of the techniques on the forum, but he's willing to try new things.

The house will be a 2x6 construction with 10ft first and 9 ft second. We have 2 questions:

In General questions | Asked By Guy Hocker | May 8 12
7 Answers

Exterior foam decision — IRC table 601.3.1 — and housewrap over foam

I am building an attached 3-car irregular shaped heated garage and trying to make it energy efficient but not break the bank. Some last minute roof changes during framing have made the attic area of garage usable space which will become a bedroom some day

I did a 4' ICF foundation because I want to heat the slab (partially by solar panels someday) there is 5" of high density EPS under the slab (craigslist bargain)
2x6 walls were necessary so the exterior walls would bear more on concrete rather than ICF foam.

In Green building techniques | Asked By tom fraser | Apr 12 12
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