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3 Answers

If you're interested in ASHRAE 62.2 and existing buildings, you should check out this email string

At ACI this year, I had the pleasure of meeting many members of a group known as the Trainers Consortium. Following a recent conference call, which I was unable to attend, an amazing email string appeared in my inbox. Barely able to keep up with the conversation, I felt that it deserved broader distribution as it covered some very important and interesting (at least to us geeks) topics. I have assembled the content and posted it on my website. Please enjoy the conversation an add your own thoughts.

In Energy efficiency and durability | Asked By Carl Seville | Jun 8 12
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

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
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