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7 Answers

New unvented attic and high humidity

Last year after a severe hailstorm the attic insulation and the entire roof deck of my 1600 sq. ft. ranch style home in Fort Calhoun, NE was replaced. With the replacement we upgraded the insulation to Open Cell Icynene spray foam on roof decking. The spray foam is at least 6-8 inches on the roof, and covers the sidewalls, soffits, and attached garage ceiling. This completely closes in the attic to the thermal envelope of the house.

In General questions | Asked By Nick Schuler | Jun 30 15
0 Answers

Net Zero vanity license plates

Phil Kaplan of Maine is proud of his "Net Zero" vanity license plate. He sent me a photo in which he poses with Bob Irving, who nabbed the Net Zero tag for New Hampshire.

Who else has a Net Zero vanity plate?

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In General questions | Asked By Martin Holladay, GBA Advisor | Jul 6 15
6 Answers

How do I get and keep air out of my geothermal loop?

We have a "closed loop" geothermal heating and cooling system. 97 wells 300 ft. deep. 4 story building. 36 water source heat pumps. 72 electric water pumps. 219 ball valves.
There is no way at the high point (attic over 4 story) to release air and no easy way to add water to displace the air. The contractor keeps trying with their big pump and tank trailers to purge the system by driving the air bubbles out through the basement. No surprise to me, having observed the bubbles in my bathtub travelling upward, this approach keeps failing.

In Mechanicals | Asked By Todd Conradson | Jul 1 15
2 Answers

Fiberglass insulation and spray foam around windows.

Would it be advisable to leave fiberglass insulation then fill remaining void with spray foam? In the event fiberglass got wet, would it ever dry if spray foam filled the remaining void? What would be the best option for insulating widows? Thank you for reviewing my question.

In General questions | Asked By tim gabriel | Jul 5 15
16 Answers

American-made Passivhaus-certified windows

Hello All,

In PassivHaus | Asked By Bob Holloway | Sep 23 14
7 Answers

Loose-fill cellulose in a small attic

It seems that the best way to insulate the vented attic on my 20x48 new house with a simple 4:12 gable roof will be to blow in loose-fill cellulose, but I wonder about maneuvering within the tiny spaces of the attic. The roof will be framed with standard trusses, with a flat drywall ceiling attached to their underside. The attic will not be used for storage or anything else. The house is in Climate Zone 2B in the Southwest.

In Green building techniques | Asked By Jeff Cooper | Jul 4 15
12 Answers

ZIP R-Sheathing Climate Zone 5?

I am considering ZIP R-sheathing for a home in Climate Zone 5. The wall assembly would be a ventilated rainscreen as follows (exterior to interior)

1. Hardie Panel siding
2. 3/4" furring/airspace
3. ZIP 1.5" R-sheathing (R6.6 total, 12-16 perms for the OSB, <1.0 perm for the polyiso)
4. 2x6 studs
5. Icynene Low Density (5.5" thick R-20, 11 perms)
6. 1/2" gypsum

In GBA Pro help | Asked By Joseph Yount | May 12 15
2 Answers

ERV exhaust up a chimney

Can I run the main exhaust pipe of my ERV into the abandoned flue of my chimney?

In Mechanicals | Asked By Fred Richards | Jul 4 15
7 Answers

Log walls and foil facing

Hi,

We are planing to add 3 inches of rigid foam to the outside of our 6 inch log home, giving the walls R 28, better then the R9 we get with just the pine logs. We will also have a ¾ rain screen under cedar siding. I have been reading that if you had a polyethylene vapor barrier in the house, to not use foam with aluminum-foil facing.

In GBA Pro help | Asked By Thomas Gardner | Jul 3 15
6 Answers

Placement of vapor retarder for radiant heat in slab

I'm building a small house (~ 1000 sq. ft.) on a full foundation and am having radiant heat tubing installed in the slab. The plumbing contractor plans to staple the tubing to the foam insulation under the slab. I had planned to put the foam over crushed stone then a 10 mil sheeting over then the slab on that as I've seen in numerous foundation diagrams. But if the plastic sheeting is over the foam the staples for the radiant tubing will poke many holes in it so that seems like a bad idea.

In General questions | Asked By Martin Frank | Jul 3 15
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