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4 Answers

Enclosure Failure Photos and Links

Please post links and photos of "Enclosure Failures" here (at this thread)

I have just started a Pinterest Bulletin Board and would appreciate suggestions
http://pinterest.com/johnkbrooks/enclosure-failures/

I will add a few links and photos soon

In General questions | Asked By John Brooks | Jun 9 12
2 Answers

Exterior foam foundation detail

I am installing two 1" layers of exterior foam. My house is built into a hill. My question has to do with the upper part that is built into the hill. I cannot dig down to the footings. I was planning on digging down about 6". I planned to do one continuous layer of foam from the point below the soil to the roof truss. I am a bit concerned with frost heave, insect intrusion, and god knows what else I may encounter as i live in the woods, since I am not going all the way down to the footings. will I be alright to run foam from 6" below the surface to the roof truss.

In Green building techniques | Asked By Kacey Zach | Jun 8 12
5 Answers

What to do with poorly installed open cell foam?

I have a 1200 sq. foot california ranch with an attached carport. Recently I had a local contractor downspray the attic. He agreed to take up all existing insulation and perform the downspray. After the job I dug into the foam in 3 places just to make sure he did it right. Unfortunately, I found 2 inches of our old, old fiberclass batt insulation under his 5 inches of open cell spray foam. Should I have him demo the whole thing and redo it, or should I negotiate a reduced rate? If so, should that be 1/2 off his $1600 fee, or more or less?

In Energy efficiency and durability | Asked By Thomas Sweets | Jun 8 12
10 Answers

Foam as sheathing, what about shear?

How is shear addressed in the foam as sheathing detail? Are some walls sheathed but others not?

I didn't see anything about this in the videos.

In General questions | Asked By David Burke | Jun 6 12
1 Answer

Choosing the right type of cellulose

I live in zone 7, western Wyoming. I am insulating my addition using 5" of cellulose, plywood, and 3" of polyisoncyanurate. I have 2 questions.

1) I have little to no knowledge about cellulose. Where can I find information on which type, blown-in, damp spray, or dense packed cellulose I should use, and what are the advantages and disadvantages of each given my cold climate?

In Energy efficiency and durability | Asked By Justine Wysong | Jun 8 12
3 Answers

Workshop shell-in for part of a steel building

Plans are to shell inside of new steel bldg for work shop.... if I screw polyiso to bottom of rafter,
(to limit thermal transfer there), then screw steel to that as shop ceiling, I would then flash with 1-2 " foam, filling the remainder with densepack blown in,
OR just blown in only densepack to top of rafter,( 6" depth, I believe).....

In Energy efficiency and durability | Asked By steven bumpus | Jun 6 12
8 Answers

Cellulose insulation

I am building an efficient and "greenish" home on Southern Vancouver Island, which has the same climate as Seattle.

I am at the stage where I need to make final decisions on insulation. Local contractors are advising against dense pack cellulose in the 10" double stud walls. Their Reasons are: Settlement over time, dust, mould, insects, rodents, labour cost of installation.

Are these worries unfounded? Obviously I want something "green" in my walls, but only if I can expect at least 50 years of service from it.

Any comment or experience would be greatly appreciated.

In Energy efficiency and durability | Asked By David Slade | Jun 2 12
8 Answers

Will I have a dew point problem in the wall cavity?

I'm a contractor living in Southwestern NH and designed an insulation envelope for a house. From inside to the outside it consists off 1/2" plaster, 2x4 with 3-1/2" R-13 blown-in cellulose, 1/2" CDX plywood and a 5-1/2" polyurethane SIPS R-32. The SIPS has 1/2" blue board, 4-1/2" of urethane foam and 1/2" OSB. All seams in the panel will be drilled and foamed.

Does the cellulose move the dew point into the 2x4 cavity?

The total R value of the wall is R-45.

In Energy efficiency and durability | Asked By James Everard | Jun 7 12
1 Answer

Follow-up question about the roof

I just posted a question about the wall cavity. I should have asked about the roof which consists of 2x12's 24" O.C. with 11-1/4" blown-in cellulose R-40+ then 1/2" CDX and over that 5-1/2" SIPS R-32.
Over the SIPS I'm going to 1" strapping vertically and than 1/2" CDX to create a cold roof. I'll have over a R-70.

My concern is with insulation in the framing cavity I might be letting the dew point move closer to the heated side of the house.

I live in Southwestern NH.

In Energy efficiency and durability | Asked By James Everard | Jun 7 12
4 Answers

Installed Cost of Solar Hot Air Panels

I'm doing a little research, to get myself more up to speed on lesser known technologies such as solar hot air panels. Does anyone have experience or knowledge of how much these systems can go for professionally installed? I know there are DIY-ers out there making them, but I'm interested in a price range for a good quality installation, and I'm not sure by what means they are priced (ie solar panels are priced by the watt/kilowatt). Any thoughts?

In Green products and materials | Asked By Mike LaCrosse | Jun 7 12
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