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4 Answers

Foam insulation/Texas

Home in central Texas (Austin)
1 story on slab
Built in 2009
Approximately 2800 sf house, 1 story
1 hvac system
Ductwork is in attic
Blow in insulation is in attic
Garage is not insulated

What would be your recommendation if we wanted
to put spray foam in the attic and close it up?
Our build out is common practice here but I think it's
terrible from an energy efficiency standpoint as our
attic is over 100 degrees all summer

In Energy efficiency and durability | Asked By tdavis3 | Aug 12 17
14 Answers

AC register condensation: Not enough ridge for adequate ridge ventilation?

I'm living in the Houston area (zone 2) and noticed water leaking from some AC registers yesterday. The home is 9 years old, 300 sq ft.

The flexible ductwork is insulated.
The register boots are insulated, and the insulation has a lot of mold. (pic attached)
There is significant water in the attic on the blown in insulation around the duct boots: not damp, really wet.
I do not think the register boots are leaking, but I guess they could have small leaks.

In GBA Pro help | Asked By Mark McFarlane | Aug 14 17
5 Answers

Steel SIPs

I know that a steel stud dosent provide a thermal break. However this company seems to have
resolved that issue.
They put 2 steel studs opposite each other on the flat, with foam in between.
Any info on this type of SIP's would be appreciated.



In Green products and materials | Asked By Brian Whidden | Jun 8 15
5 Answers

how to insulate around a ceiling light can in and attic and loose as little thermal loss/ leakage as possible?

If one uses compact floresent bulbs which do not get as hot as incandesent, how close can you get the insulation next to the light can?
.........Terry Nordbye - North Bay Green

In General questions | Asked By terry nordbye | Jan 29 09
4 Answers

FORCE/2 Rental Locations in NY 10956 area, I am having trouble finding a place to rent a FORCE/2 for dense packing of walls.

I put up my fabric a while ago without first checking my area for a force/2. I am getting to the point where I am thinking of buying one just to do my project, which is relatively small, I a guessing a day with the right machine. All the rental places near me that I have contacted have the force/1. I am willing to travel an I am often between Albany new have and Washington DC. Please share any know rental locations.


In Green products and materials | Asked By Gregg Mastropolo | Aug 8 17
5 Answers

Insulated cathedral ceiling question

I reviewed your article on this topic (http://www.greenbuildingadvisor.com/blogs/dept/musings/how-build-insulat...) but am hoping to get your thoughts about my specific variation in mind.

I'm constructing a small (12x24) guest cabin with a "modern" post and beam frame. The plan for the (cathedral ceiling) roof assembly is v-groove over the rafters then 2 layers of rigid polyiso sheets staggered and taped, house wrap then Advantech screwed to the rafters followed by asphalt or fiberglass shingles over felt paper or whatever material is appropriate for the product.

In General questions | Asked By MF-NH | Aug 12 17
5 Answers

Puzzling over my blow in insulation options

I have a wonderful 1897 house in Portland, Oregon (zone 8b - not so cold, not so hot, so very rainy!).

[Editor's note: Portland, Oregon is in Climate Zone 4C.]

I don't have to worry so much about the temperature extremes but it rains here, famously, all the time. I would like to insulate my exterior walls and need to do blow in because I'm not opening up the walls. I am also going to insulate the attic which is currently open (looking to do along the roof line probably with spray in foam).

In Energy efficiency and durability | Asked By Mrmiller117 | Aug 14 17
4 Answers

Method to use permeable insulation at cathedral ceiling or sealed attic?

The oft repeated rule here is that closed cell spray foam is required at cathedral ceilings and the underside of unvented attics. The reasoning is open cell spray foam, or cellulose, or other loose insulation is vapor permeable, and will thus allow moisture from the house to migrate through to the sheathing, and cause the sheathing to rot. However, the big downsides to closed cell foam are the environmental concern, and the cost.

This article:

In Energy efficiency and durability | Asked By C L | Aug 13 17
7 Answers

Raised heel trusses and window height in elevation

I am asking my builder to include raised heel trusses in my new house, though I doubt my plans reflect that in the elevations. So, what are the implications of this?
- Should window heights be adjusted?
- Overhang distances?
- How will this affect the look of the house?


CZ3A, Greenville, SC

In Green building techniques | Asked By Norman Bunn | Aug 9 17
5 Answers

Temporary bracing for small trusses

I'm installing standard trusses with a 20' span, 2' overhangs, and a 4:12 pitch for a simple gable roof. The truss drawings indicate that the only permanent bracing needed is sheathing on top and a drywall ceiling directly attached on the bottom, both of which I'll install.

In General questions | Asked By Jeff Cooper | Aug 12 17
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