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28 Answers

I would like to better understand the significance of thermal bridging in light frame / wood construction.

Some information about thermal bridges and thermal breaks:

Thermal Bridge
"Characterized by multi-dimensional heat flow, and therefore they cannot be adequately approximated by the one-dimensional models of calculation typically used in norms and standards for the thermal performance of buildings (U-values)."

Thermal Break

In Energy efficiency and durability | Asked By Daniel Ernst | Jan 18 11
15 Answers

What is the process to dense-pack cellulose in a double-stud or Larson-truss wall? Is this something that an owner-builder can do with the cellulose blowers that can be rented from the local building supply store? What is the best way to insure the proper density in the wall cavity?

In Energy efficiency and durability | Asked By John Hess | Sep 17 10
1 Answer

Long-time GBA readers will remember our news story on the tragic fire in Hudson, Québec last year -- a fire that destroyed Sevag Pogharian's net-zero-energy house when it was only weeks away from completion.

The initial investigation indicated that the fire may have been caused by excessive heat buildup from the exothermic reaction that occurred during installation of the home's spray polyurethane foam insulation.

Today I received an e-mail from Pogharian, who wrote:

"Hello Everyone:

In Green products and materials | Asked By Martin Holladay | Feb 18 11
3 Answers

I read with interest the article on roof venting by Joseph Lstiburek in the Sept. 2011 issue.
I am halfway finished with a mountain home in southern Colorado, climate zone 6. I will
insulate soon. I had planned to vent as much of the roof as rasonably possible and have

In GBA Pro help | Asked By John Reeder | Aug 15 11
1 Answer

I have an 8" ducted de-stratification system and would like a single fan (hopefully very quit) with a three position switch. The open floor plan two story structure in WV enjoys warm air blowing on the insulated slab in the winter and cool air distribution at the ceiling during the summer.

In Mechanicals | Asked By Al Cobb | Aug 15 11
8 Answers

Now that we’ve reached the conclusion that (in the current market) it will be more affordable to buy a resale and remodel/upgrade than to custom build and “do it right,” I’m reading the GBA advice from a different angle.

In Energy efficiency and durability | Asked By JoeW N GA Zone 3A | Aug 15 11
9 Answers

I live in Westchester, NY. The exterior of my house is vertical Cedar siding (with stain) over Plywood sheathing, which I believe has house wrap over it. I am redoing 2 bathrooms. My plan was to blow closed cell foam into the exterior walls to cut down on air movement and give me more insulation (the walls are 2 x 4) The banthroom used to get quite cold. I was planning to put blue board or paperless wallboard over the non-shower walls. In the shower (one of the walls of which is an external wall), I was planning on using cement board and the Schluter Kerdi and shower system.

In Energy efficiency and durability | Asked By Richard Cohn | Aug 14 11
0 Answers

So the City of Dallas is going to implement a program where Certified Verifiers will be allowed to do plan reviews. I’m curious to know if other cities or municipalities have similar programs and what you’ll think of it… please chime in… http://www.greenbuilttexas.com/gbt-program-news/city-of-dallas-to-allow-...

In General questions | Asked By Armando Cobo | Aug 15 11
3 Answers

A deep energy retrofit project in Minneapolis will be utilizing a Larsen Truss type approach to insulating outboard an existing home while tying into a new addition with a deep cavity of cellulose insulation.
High R-value, thick wall applications of dense pack cellulose have little precedent in this area so a local insulation contractor is offering dense pack demonstrations of walls they have mocked-up using 9 1/2" and 12" I-joists.

The demonstration will be held on Tuesday, August 16 starting at 10am and is open to the public.

In Green building techniques | Asked By j chesnut | Aug 11 11
8 Answers

I live in Tucson, Arizona which is generally warm and very dry, with winters with overnight freezes and wet summers with periods of high humidity.

In Green building techniques | Asked By Ryan McCulley | Aug 14 11
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