Q&A: A Forum for Green Building Experts and Beginners

[Click map to enlarge]

Please register for a free account or sign in to ask and answer green building questions.

The usual rules of courtesy apply:
1. Be nice.
2. If you can't be nice, be polite.
3. If you can't be nice or polite — well, please be brief.

To attach a photo or illustration:
Under the box labeled "More explanation," look for the words "File attachments."
Click that, and you should be able to attach a photo.

Thanks for joining the conversation!

11 Answers

LPG infloor heat with HWH with a heat exchanger in the HWH is too expensive to run!

I have the above home on a monolithic slab. ...LPG to run the HWH and a heat exchanger pipe running through the HWH to heat my floor...TOO DANG EXPENSIVE TO HEAT MY HOME THAT WAY! Suggestions on how to make it more efficient would be appreciated. A air to water heat pump? A heat pump water heater with a heat exchanger pipe running through the HWH? A solar system of some sort?

In GBA Pro help | Asked By Ed Jones | Jan 25 15
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
14 Answers

Double Staggered-Stud Wall vs. 2x3 + Foam Strip + 2x4 Wall

My new house will be in a part of climate zone 2B in Arizona where the winter nights often dip into the 30s and the summer days often rise to 100 with around 45 days of "monsoon season" mostly in August when we'll get an hour of thunderstorms once or twice a week. We have moderate to severe termites.

In Green building techniques | Asked By Jeff Cooper | Jan 23 15
12 Answers

Minisplit setup for New Jersey, 750 sq. ft. house over crawl. Bouncing my HVAC contractor's plan off you guys.

The short. I have a 25x30 rancher over a currently vented crawl. It sets almost perfectly south facing on the 30ft long side. No tree shading on south or west. Deciduous tree shading in the east and some on the north side. It's two bedrooms one bath, kitchen and living room. Standard stick frame 2x4 construction and vinyl siding. House was built in 1963 in a post WWII development.

Bedroom1: 10x12
Bath: 5x9 rough estimate
Kitchen: 9x11
Living: 14x14 rough.
Short hallway off living room with bedrooms at the end: 4x7

In Mechanicals | Asked By Lance C | Jan 16 15
2 Answers

Will adding more insulation in basement create a problem?


I've got a large basement space which I'm renovating into a living area. It's in zone 5, Ontario, Canada.

Floor, and Lower 2/3 of walls are bare concrete, upper 1/3 is fiberglass insulated stud wall with drywall.

Walls had been insulated with 1-1/2" of paper faced fiberglass bats between furring strips on which hung wood paneling. Paneling and fiberglass have been removed after 20-30 years, without any signs of mold.

In General questions | Asked By Richard Baumgarten | Jan 26 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
Register for a free account and join the conversation

Get a free account and join the conversation!
Become a GBA PRO!