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2 Answers

Crawl space insulation installation. Bids include spray foam and fiberglass

Home built in 1962, without insulation in crawl space below the floors. I have bids for R-19 closed cell spray foam, or fiberglass. The area is Seattle. Any advice? Thanks.

In Energy efficiency and durability | Asked By Caroline Orr | Sep 14 12
2 Answers

Dew point calculation vs location of air barrier.

The dew point at the first condensing surface often is considered important in judging the robustness of a wall design. In the case of adding external insulation, a minimum thickness is required to keep the sheathing above the dew point.

The dew point, as far as I have seen in discussions, has been based on that of inside air at room temperature and some appropriate relative humidity. This gives a "safe" answer and would seem to assume one of two things.

In Energy efficiency and durability | Asked By Dick Russell | Sep 14 12
2 Answers

how to order a trusses

pre eng roof trusses

In General questions | Asked By juan godoy | Sep 14 12
0 Answers

GBA is reviewed by El Nuevo Constructor

Sergio Grado of El Nuevo Constructor has published a review of the GBA website.

Sergio wrote, “Este sitio es mi primera parada cuando tengo unos cuantos minutos libres. Contiene videos, reseñas de productos y esquemas detallados de los que puedo aprender mucho. También contiene un blog en donde se discuten distintos temas sobre construcción.”

In Green building techniques | Asked By Martin Holladay | Sep 14 12
6 Answers

Peel & stick - Under or over the strapping

I'm in the process of building a thick foam covered wood framed house.
It's a 2x6 wall with 2.5" of XPS, followed with 1.5" of polyiso foil faced and taped. In order for me to apply my vinyl siding i need to add 1x4 strapping and 2x10 windowbucks as the foam is so thick

I'm uncertain on whether of not to put the peel and stick membane over the 1x4 strapping or under?
My windows are new contruction and have nailing flanges

I have included a picture of what is going on... if i go over the 1x4

In General questions | Asked By Brian Krmpotic | Sep 10 12
1 Answer

What is the perferred way to ventilate a basement?

I built a house in VT zone 6A. The unfinished basement has a musty smell to it. The 2 floors of living space are fine.

I only have 2 (1'x2') basement windows in the east side of the house. I'm planning on finishing the basement and looking to install a HRV ventilator for the basement only. The house is heated with radiant floor heat and wood stove. Basement is 1,400 sq ft.

In Energy efficiency and durability | Asked By Tom Tyrrell | Sep 13 12
6 Answers

Why would there be 2 air returns in a bedroom with only 1 supply?

I recently purchased a tri-level home built in 1962. It hasn't seen a lot of love over the years so I'm trying to make some cosmetic improvements before moving in. In each of the 3 bedrooms there are 2 air returns, one near the floor and the other directly above it about 6 feet up, on the wall opposite the supply registers. For aesthetic reasons I would like to close off the upper returns but hesitate to do so without understanding why there are 2 of them and is closing one an OK thing to do. Any advice would be appreciated.

In General questions | Asked By Sue DeChant | Sep 6 12
1 Answer

Will this insulation assembly work?

I have a situation and I was wondering if I could get some input on an assembly I may be doing. Please refer to the PDF drawing I have attached to this. it will explain a lot more than words can. I am in Washington State in Marine Climate 4. I am working on a remodel of my house.
I realize there are many better ways that this assembly could be done, but that isn't what my questions are about.
Top two drawings of attic cavity:

In Energy efficiency and durability | Asked By Spencer Burnfield | Sep 12 12
4 Answers

Why doesn't the website work?


In General questions | Asked By Spencer Burnfield | Sep 11 12
26 Answers

Can I install XPS foam board over plywood sheathing, when using concrete board siding?

I was also going to fill the interior stud walls with Fiberglass bats backed with 6 mill vapor barrier. I'm located in southern ontario Canada; just outside of Toronto.

In Energy efficiency and durability | Asked By Mike Tew | Sep 9 12
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