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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
1 Answer

Insulating over exterior brick - Do's and Dont's?

Hello, short time lurker, first time poster.

My wife and I bought a small pre-WWII home last fall. Sadly it was built in an era where the very concept of insulation and efficiency were unheard of.

It's a 1.5 story house approximately 1250 sqft. Double brick exterior. My goal is to energy retrofit as much as possible over the next 2-3yrs. That will start with insulating the attic this fall but I need a solution for the walls.

In Energy efficiency and durability | Asked By user-6901433 | Aug 13 17
2 Answers

Flash and Batt - what type of drywall?

Hi Martin:

I have just completed a Flash and Batt insulation in the basement of our home:
installed in 16" 2x8 bays - 2" Dow Corning Foamular and Roxul R22. All seams, foamed, caulked and taped.

Can I use regular drywall on top of this or do I have to use a special Paperless Drywall - I was under the impression that Regular Drywall is actually a vapor barrier and would have the same effect of retaining moisture as 6 mil poly???

Mark Kozlowski
Crawford Bay
British Columbia

In Energy efficiency and durability | Asked By Mark Kozlowski | Aug 13 17
5 Answers

Questions about installing EPS above concrete.

I'm in climate zone 6A, I think. Halifax, Nova Scotia. I've read that the best approach to insulating an existing basement floor is to install a continuous layer of 1" thick EPS foam over the concrete, with taped seams, and two layers of either plywood or OSB on top.

1) If EPS is vapour permeable why use tape to seal the seams?

2) I have existing partition walls that are screwed to the concrete with foam gasket in between, please tell me I don't need to remove them and put the foam under the walls?

In General questions | Asked By Calum Wilde | Aug 12 17
8 Answers

550' main water line to house : help me choose a suitable pipe

My driveway is 550' long, and the water meter is at the road. So far I have determined I should be happy with a 1.5" ID pipe, for the flow I am considering. I was all set to pull the trigger on HDPE pipe (NSF rated, 200 PSI), until I read some articles that claim this type of pipe becomes brittle with time when exposed to water disinfectants (read chlorine, chloramine, chlorine dioxide etc.), anything the utility puts in the the great lakes water to make it "safe".

So back to the drawing board. The options:

HDPE CTS 200 PSI pipe

In GBA Pro help | Asked By Mai Tai | Aug 10 17
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