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8 Answers

Rigid foam on inside of stud cavity?

Looking to maximum the insulation levels as high as I can and not use spray foam due to price.

In Green building techniques | Asked By kurtis wiedmann | Jan 25 15
4 Answers

SHGC high-solar-gain windows current list

Could we list a few US window companies where SHGC windows are available?

Also 2115, what window company are all of you using, in my area, (northern US)

My climate 6A

My area Andersen, Pella are the higher end choice, mainly because that's what's our lumber yard promotes. Some Marvin... The tract builders have lesser known names, all vinyl. I will list them after I get some names.

I only know of one other builder that cares about windows with high solar gain.

In Energy efficiency and durability | Asked By aj builder, Upstate NY Zone 6a | Jan 25 15
2 Answers

I need to replace my gas furnace

Hello to everybody at GBA.

My gas furnace and AC system is starting to get old and I'd love to replace it with a heat pump. As I already have ducts, it seems to me that a ducted system would be best, but I can't figure out if that would really work.

In Mechanicals | Asked By Martin Holladay | Jan 26 15
2 Answers

Home Depot Offers High SHGC Glass

I just ordered some windows for the south side of a pretty good house in Colorado.
U=.26, SHGC=0.69

Under $300 for a big fixed vinyl window from Jeld-Wen.

When you sit down with somebody in the millworks dept., just make sure you get the Cardinal LoE-180 glass. Careful, they might try to talk you out of it, because they don't understand passive solar energy.


In Green products and materials | Asked By Kevin Dickson, MSME | Jun 17 14
2 Answers

Vaulted ceiling insulation

I'm fixing up my garage, looking for some insulation guidance. The framing was done by somebody's grandfather in the 40's and it's real crazy, but then, it's stood there in southern CA earthquakes for about 70 years so I'm not too worried about it. Anyway, I'd like to attach T & G or drywall directly to the roof rafters, to keep the vaulted look but can't figure out how best to insulate it since there'd be no attic.

idea #1: put Dow Tuff-R rigid insulation in between the rafters, fill in gaps with Great Stuff foam.

In Energy efficiency and durability | Asked By Robert Page | Jan 25 15
1 Answer

Insulating an apartment cathedral ceiling built with 2x10s @ 2'6" on center

Hi Folks,
I'm trying to build a "pretty good" little apartment - and I'm interested in recommendations on how to best insulate the ceiling - as noted , rafters are 15 ft long 2 x 10's on 2'-6 ctrs., with existing tin roof and the usual rolled out insulation package under the tin. (supposedly R 4 but is smashed to R-0 betw tin roof and rafters) I'm planning to run perpendicular battens with thermal breaks to span the 2'6" gaps of the sheetrock installation.

Obvious options:

1) just stuff and fluff (2) 16" wide R38 batts and retain w crossways battens

In Energy efficiency and durability | Asked By Chip Chandler | Jan 26 15
3 Answers

Advice on rough finished new construction, Zone 5, top floor

Background: I did what I said I'd never do and bought a big house. I'm trying to house several older family members and my kids at this time in my life and I couldn't help it. The style, over built owner construction and 8 hard wooded acres hooked me. And the price was right. It's all finished except for the top floor. Which is where most of my advice will be needed. It's located in Middlesex County ma.

The 1250 sqf top floor has dormers and 1 skylight.. 2x6 walls and

In General questions | Asked By stephen edge | Jan 25 15
4 Answers

Where to buy competitively priced PV panels?

Hi there,

For years I've been reading here about how the price of PV has dropped and dropped. I believe that, yet I'm unconvinced that my web searches are showing me those most-competitively-priced PV panels and accessories (particularly since improvements continue to be made, and older models may sit on the web to be unloaded at not-very-competitive prices).

I realize the folks working for GBA may possibly not feel comfortable listing some good places to buy PV panels (or, maybe it's not a conflict), but in any case, I'd bet some forum members could advise...?

In General questions | Asked By Minneapolis Disaster, 6B | Jan 25 15
5 Answers

Bathroom exhaust fan damper

I was just installing a Panasonic whisper green select exhaust fan. I've heard that Panasonic makes quality fans and I liked the options that the fan has, but I was unimpressed with the damper. Its flimsy plastic and it doesn't seal the fan at all. I can clearly see through the fan and down to the floor through two big gaps on each side of the damper. I remember the last fan I installed was a cheaper brand but it had a nice metal damper that seemed to seal quite well. Is there anything that I can do to seal the fan better? Would installing a duct damper be wise. Thanks for any help.

In Energy efficiency and durability | Asked By Kevin Schramm | Jan 25 15
8 Answers

Wall vent vs. roof vent

We are installing a custom wood range hood and can't decide between venting through our wall or heading through the roof. The duct is 6" round. Going through the roof the run would be about 3-4' straight up. Roof is pitched about 5-12 and the vent cap would land right around 30" from the eave.

The range sits on an exterior wall, so heading though the wall would give the run a 90 degree turn and about 2' of ducting. The siding is 4" lap fiber cement. Any pros or cons or suggestions to persuade me one way or another?

In Mechanicals | Asked By Matt Cibula | Jan 25 15
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