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0 Answers

I hear Tremco acoustical sealant touted here but it's not available anywhere locally that I've found. Is there really much of a difference between Tremco and any other butyl caulk when used for air tight drywall and maybe some roof flashing (metal roof)?


In Green products and materials | Asked By Alan Gage | Aug 17 11
3 Answers

Where can I find information about the inherent efficiency of dwelling units that share common walls or floors?

In General questions | Asked By josef chalat | Aug 16 11
4 Answers

We are buiding a conventional stick frame house. We have a number of sheer walls, so the entire house already has a layer of OSB. I would like to add exterior foam. Is this possible since I already have OSB on the house? Would 1" suffice? Since I live in Sacramento (Zone 3C) I am not going to worry about a vapor barrier or moisture issues. I'm trying to get my contractor to buy into this, and he has asked me to bring him a sample of the foam. Is there a type you recommend for my climate/situation? Thanks.

In Green building techniques | Asked By Laura Sainz | Aug 16 11
7 Answers

What sound insulation product (for a city apartment ceiling) is both most effective and least toxic?

In Green products and materials | Asked By Ellen Leopold | Aug 16 11
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
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