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16 Answers

American-made Passivhaus-certified windows

Hello All,

Asked By Bob Holloway | Sep 23 14
1 Answer

Had a 50 inch water heater replacing it with a 59 1/4 inch one will there be any problems because of height difference

Does the height difference cause any problems with installation.

Asked By Anthony Wells | Jul 5 15
1 Answer

Spray-applied acoustic sealants

I have already found couple of articles at GBA about sprayable caulk that is used to air seal envelope: EcoSeal and EnergyComplete. Is there anything newer coming up on the market? I only ask because our builder was approached by Lumber84 to become a test house for air sealing with acoustical sealant... We still don't know what it might be and what properties and VOC, etc.
Thanks,
Lucy

Asked By Lucyna de Barbaro | Jul 5 15
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.

Asked By Jeff Cooper | Jul 4 15
5 Answers

New Unvented Attic and High Humidity

Last year after a severe hailstorm the attic insulation and the entire roof deck of my 1600 sqft 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. I've been monitoring the relative humidity levels of the house for the last year.

Asked By Nick Schuler | Jun 30 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

Asked By Joseph Yount | May 12 15
1 Answer

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.

Asked By tim gabriel | Jul 5 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?

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.

Asked By Thomas Gardner | Jul 3 15
15 Answers

Boiler upgrade recommendation?

I’m currently looking to upgrade my old boiler as it developed a small crack and is leaking. My current boiler is a P-468U-wt (151,000 btu/hr) Weil-McClain oil-fired boiler with a 40-gallon hot water holding tank.

I’m getting two different suggestions from two of my plumbers and would love some input on their recommendations. One recommends replacing it with an Energy Kinetics System 2000 and the other one is suggesting a Navien Combi-boiler.

Asked By Joe Pavia | Jul 1 15
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