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3 Answers

We are building a new home in NW Montana, zone 6. We have a great room with a vaulted ceiling and a vented roof above. Going to use cellulose to r49 above great room. I want to make sure that I get the ceiling profile right. I have been told to put poly on ceiling then osb or plywood and lastly the metal we want to use for the interior finish. Will this work without causing moisture problems?

Any draw backs to using metal roofing on the interior ceilings as finish?


In Energy efficiency and durability | Asked By Rod Cleveland | Feb 10 12
4 Answers

We are trying to decide on window glazing options for our east facing windows in San Francisco. Our window manufacturer uses Cardinal glass and offered us two Low-e options.
Low-e 277 and Low-e 180.

In Energy efficiency and durability | Asked By Donovan Corliss | Feb 9 12
4 Answers

I am wondering if anyone has any advice on properly flashing window and door penetrations when using a panel type siding. My specific project specifies LP Smartside reverse board and batten siding in 4x8 sheets. The windows and doors are aluminum clad, with a 1x4 picture frame trim detail.
I am mainly concerned about the detail at the head, where it should be flashed. I would like to avoid just cutting out a hole in the panel for the trimmed and flashed unit, then relying mainly on a caulk joint, but maybe properly detailed, this is the simplest option.
Thanks for any help.

In GBA Pro help | Asked By Pete Archer | Feb 9 12
9 Answers

Hello to all,

Well here is my conundrum. I live in a house that was built in 1983, and it was built using the minimum materials in every aspect. The house is a modern/contemporary with vaulted ceiling up to 28' high. Saying that the roof was framed using 2x8 rafters, and yup r-19 insulation faced bats. The walls are 2x4 with what seems to be at best 4 mil vapor barrier, r-11 unfaced bats, and 1/2" Celotex w/5/8" t-111 exterior siding.

I need to bring the r-value up to as (close) to minimum code. Our local code call for r-38 ceiling, r-19 walls.

In Energy efficiency and durability | Asked By jason hood | Feb 8 12
4 Answers

I am looking for a very energy efficient way to build a house and to avoid all mold issues inherent with plastic wrapped houses that can't breathe. Living with mold greatly increases symptoms of Lyme disease.
Got any suggestions?

In Green building techniques | Asked By Margery Brache | Feb 8 12
3 Answers

What other reasons to fasten down sumps?
1) Reducing moisture vapor in basement
2) Air infiltration into house through any holes
3) back flooding into basement

In Energy efficiency and durability | Asked By Rick Jenkins | Feb 9 12
10 Answers

I read this case study by David Fridley of Lawrence Berkeley National Laboratory:

Then I remembered one of Martin's blog entries:

The case study indicates that when evaluated on a annual basis, the embodied energy of a residential building is roughly equal to the energy consumed for its operation. The case study assumes a 30 year life-span for these buildings which is average in China.

In General questions | Asked By Lucas Durand | Aug 21 10
5 Answers

Dear Sirs: I am building walls on the inside of my kitchen and was wondering what is the best way to insulate the walls. I want to use paper backed insulation with plastic. Should I put the plastic on the back side of the wall then insulate or should I insulate and then put the plastic on top of the insulation on the inside of the walls. Any help and information that you could furnish me will be greatly appreciated. Thanks. jbrock2751@comcast.net

In Energy efficiency and durability | Asked By John Brockway | Feb 9 12
61 Answers

I stumbled on this ancient video recently and heard a sort-of contrarian statement:
"don't EVER say that hot air rises..because that AIN'T so"
(just watch the first 1:30 minutes)

"What happens is that the less dense air is pushed up by the colder air"

I had never heard it put that way ...hmmm.... very interesting

So yesterday Allison Bailes Posts a Blog on the same subject.

In General questions | Asked By John Brooks | Jan 31 12
2 Answers

We've had to move some plumbing lines in a freshly spray foamed (open cell foam) insulated wall. This requred us to remove some of the insulation. What's the best way to refill the insulation here without calling out the original applicator and paying his $500 minimum trip charge?

In Energy efficiency and durability | Asked By Dave Sykes | Feb 8 12
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