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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
2 Answers

What's the best way to integrate rain water to a condo system?


First of thank you for having such a wonderful forum to share infornation on. I have found this place very usefull in the past.

To my question: im designing a 7 story medium sized condo that will house 6 families. Im thinking of integrating rain harvesting to the building as we some times get droughts and i hate to see all that rain water go to waste. I think it should be regulation to have some sort of backup water sytem just incase the mains dry up. But for now will just be using rain water for the watering closet.

Some numbers:

In Mechanicals | Asked By Osman Naskali | Jan 24 15
2 Answers

Windows - Canned spray foam vs. ExoAir foam tape

I noticed that builders will use canned spray foam to fill in the gaps between the window and the window bucks. The spray foam is messy and needs to be trimmed back on the interior and exterior since trim work cannot be done properly. I also question spray foams ability to expand and contract as window frames do over the course of the life of the home. I also have seen smoke pencil tests done after spray foam and there are noticeable air gaps between the window frame and buck.

In Green products and materials | Asked By Peter L | Jan 24 15
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