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3 Answers

Closed-cell spray foam in new commercial construction

Hi. I would appreciate some input on the wall and roof assembly of a new commercial building in the Buffalo, NY area (climate zone 5). The building is a simple 24'x40' box with 10/12 gable roof.

Code requires R-38 for the roof and R-13 (wall cavity) plus R-3.8 continuous for the wall.

In Energy efficiency and durability | Asked By Tobias Westermann | Nov 5 12
13 Answers

Foam sandwich concerns

I suspect I know the answer to this already, but it bears exploring as the "risk" will impact my wall design for the future house.

In Green building techniques | Asked By Kent Jeffery | Nov 4 12
3 Answers

Best way to vent (or unvent) roof?

I am looking for suggestions on how to handle insulating this roof. The main problem is that where there are gables, there aren't any eaves for venting. The house is in Zone 6, I am looking to get R100 by insulating the rafter plane with dense pack cellulose. Am I better trying to build out a channel from an open eave to create venting or going unvented by fitting 5" of foam in the upper roof and finishing with cellulose. Neither idea seams great and spray foam would be very costly.



In Energy efficiency and durability | Asked By Brian Van Handel | Nov 4 12
3 Answers

Need help deciding where to install Panasonic FV-04VE1 ERV in new house

Need help deciding where to install Panasonic FV-04VE1 ERV in new house. ~1650 sq ft. open living room/dining/kitchen. Also plan on installing a second Panasonic ERV in the basement but that is easier. Any help deciding where to install my main floor ERV would be much appreciated. Floor plan attached. Thanks.

In General questions | Asked By Patrick Schoolen | Nov 5 12
2 Answers

Looking for siding contractor in western Mass./Connecticut Valley

Our house, built in the early 1970s, has some rot in and under the siding on the north side, a gable end. A contractor recommends removing all the clapboards on that side, then removing and replacing all the plywood sheathing. I asked if we could improve on the insulation when the wall was opened up, but he said no, we can only replace what’s there. (The house has ordinary frame construction and fiberglass insulation – I believe it’s about R-11, but I can’t find a record.)

In General questions | Asked By Patricia Appelbaum | Nov 5 12
2 Answers

Can I justify a hot tub?

40 years of carpentry are catching up: my bones are getting creaky. I never thought I'd want a hot tub until I used a friend's on a few chilly mornings, and now I see how it could become habit-forming.

Is there any way to make an outdoor hot tub acceptably green, without solar power? Could I wrap enough insulation around it to make it efficient?

Climate zone 4, natural gas available.

In Energy efficiency and durability | Asked By David McNeely | Nov 5 12
6 Answers

What cold wall/vapor profile system is practical to use in Whitehorse, Yukon?

Dear Sirs
Would you please guide me in understandingthe design for our new house ?
We live in Whitehorse,Yukon Territory, so our goal is super insulated, because
of our cold climate.

While Yukon is mostly a Subarctic/Arctic region, Whitehorse is much milder than the interior Yukon.
For example:
Average January temperature
Whitehorse -17.7C Old Crow -31.1
(the record daily low was -52.2 in 1947)
Average July temperature
Whitehorse +14.1C Old Crow +14.6C

In GBA Pro help | Asked By D'Arcy Olynyk | Nov 1 12
3 Answers

I love rotten wall sheathing

For an upcoming article, I'm looking for photos of rotten OSB, rotten plywood, and rotten sheathing boards. The topic: all about wall rot.

If you have a photo you are willing to share, post it here or e-mail it directly to me:
martin [at] greenbuildingadvisor [dot] com.

If you think you know the source of the moisture, send that information along with the photo.


In General questions | Asked By Martin Holladay | Nov 5 12
7 Answers

Anyone seen a defective exterior paint finish on Serious fiberglass window frames?

It took me some time to specify Serious Windows, after Serious bought Alpen (note: Alpen has recently "bought back" the fiberglass window line), but in the last few years I've specified them three times. The first were white, the second painted almond and this third time we went with bronze, all standard colors. The bronze windows were delivered last month with a defective paint finish on the exterior; looked like an adhesion problem with a touch-up or second coat.

In GBA Pro help | Asked By Rachel Wagner | Oct 30 12
0 Answers

A lively debate by several bloggers

GBA's news story on the petition asking PHIUS to choose a new name for any standard deviating from the current 15 kwh per square meter Passivhaus standard has generated many comments. In fact, the debate has been picked up by several bloggers in two countries.

Here are links to the latest articles on the topic:

In PassivHaus | Asked By Martin Holladay | Mar 27 12
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