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7 Answers

Alternative to a Frost-Protected Shallow Foundation

I wanted to build my house with a Frost-Protected Shallow Foundation. I've got a set of plans that I've been running by builders, and most don't have any experience with them. The general response is "Foundations need to go down 42 inches around here."

The general design for the house is:
Single floor
12" Double walls with a bearing exterior wall.
FPSF Monolithic slab with full sub-slab insulation
Rochester, NY Climate Zone 5

I have a couple motivations for the FPSF:

1. I want the house to be accessible (not too many steps)
2. I don't really want a basement.

In Green building techniques | Asked By John Ranson | Aug 15 17
1 Answer

Slab and frame issue

What product would be best to seal between a slab foundation and the frame? Am getting outside bugs in and I was told by our HOA that others have had this issue.

They suggested an spray foam insulation.

In General questions | Asked By Kim9131 | Aug 15 17
12 Answers

Full dimensional 2x4s or new 2x6s in roof? And Roxul or closed-cell foam?


In Energy efficiency and durability | Asked By Rob Manheimer | Aug 8 17
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
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