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2 Answers

Waterless vs. ultra efficient urinals

I am planning on installing one in my house & want to know if anyone has an opinion or experience w/ which would require less maintenance over time.

In Green products and materials | Asked By Eddy Hogan | Jan 24 14
1 Answer

Damper control motor

I have a 36" whole house exhaust fan mounted in an attic dormer with a gravity damper. I want to add a damper control motor. Problem- the fan is a two speed, wired from down stairs and the damper motor needs only one input. I think I need a relay to make it work. What kind of relay is required? Thanks.

In Mechanicals | Asked By Jim Phillips | Mar 1 14
2 Answers

Prepping the rim joist for spray foam in cold weather

I live in upstate NY (climate zone 5 or 6; I'm right on the line) in a brick house that was built in 1850. My foundation walls are at least 14-in. thick stone (with mortar joints). I believe the house is balloon framed, but I haven't lived in it long enough to figure that out yet. I've heard from the previous owners that there's blown cellulose between the walls and the brick. There's some evidence on the exterior that this might be true.

In Energy efficiency and durability | Asked By Chris Ermides | Feb 13 14
3 Answers

What is the best flash-and-batt approach for a low-pitch unvented cathedral assembly?

New 2600 sf house is a low-pitch 1 1/2 : 12 shed standing seam metal over plywood sheathing on 1 3/4x14 LVL's 24" o.c., drywall ceiling. Zone 3 SF bay area; site is a north facing downslope just into the hot-dry 3B Zone, but sharing much of the climate of San Francisco's 3C. I have in mind 2" closed cell foam, either rigid panels sealed in place to joists with spray foam, then filling remaining cavity with 12" net thickness R38 batts; or 2" nominal spray foam, with 12" of R-51.6 blown in spider fiberglass secured by netting.

In Energy efficiency and durability | Asked By brian rawlinson | Feb 27 14
5 Answers

Insulating scissors trusses — best practice or economics?

I'm going to build a one story house with walk out basement in northern Idaho, east of Coeur d'Alene. The main roof will be scissor trusses with a 16" heel. With an 8/12 pitch roof and 4/12 pitch ceiling. Due to the spans, there will probably be a 7' to 8' space at the peak between the roof and ceiling. The roof will be standing seam metal and the finish ceiling will first get a taped drywall ceiling and thane 1x T&G boards over that.

In Green building techniques | Asked By James Mills | Feb 28 14
1 Answer


Well, I recently built a new home, (its of sip construction) and it would appear that my attempts to ensure it airtightness have been quite successful. I haven't actually tested or measured its airtightness so my opinions are solely based upon observation. I didn't install a HRV although technically the code called for it because my experience with operating HRV's has been mostly negative.

In General questions | Asked By Glenn Thornborrow | Feb 28 14
5 Answers

Recommendations for finishing a house on island in SE Alaska?

I purchased a partially completed house on a small island 80 miles south of Juneau. The 40x30, 2.5 story house is built on pilings with 2x12 floor joist on 16" centers, 1x6 walls, 16" oc, a combination of 5/16th osb and plywood, wall sheeting, all windows and doors installed, a finished raised seam metal roof, second floor (2x12, 16"oc and stairway done, and minimal inside framing accomplished. The amount of framing in the house shell is really overdone!

In GBA Pro help | Asked By Michael Parnell | Feb 28 14
4 Answers

Strange venting and ice dams

I visited an acquaintance's house last night for another "informal
energy audit", as he was complaining of ice dams bad enough to
bring a little bit of water drip into the top of a couple of window
frames. Boston area, zone 5, and our thermal rollercoaster of
the winter we've been having. The house is typical early-nineties
vintage split-level, simple 6-in-12 or thereabouts roofline with
maybe 5 - 6 inches of blown-in fiberglass on the attic ceiling.
Ridge vent most of the way along. The rafter bays have those token
styrofoam vent channel pieces sitting at the eaves but not nearly

In General questions | Asked By Hobbit _ | Feb 28 14
13 Answers

Envelope Renovation in 2A: Part 1- Attic

I'm going to break this down into 2 posts...attic and wall, with the attic/wall intersection here.

Brief background on existing conditions:

1970 2-story home (2500sf) here in Seabrook (SE Houston), a very hot very humid climate in a 110mph windzone

1st floor: 85% brick veneer on 2x4 stud backup and faced fiberglass batt insulation (sheathing/weather barrier unknown)

2nd:floor: is 12" Masonite lap siding attached directly to studs (yes...no sheathing)...again with the fiberglass batts

In Energy efficiency and durability | Asked By Jon Pippert | Feb 27 14
3 Answers

Air Handler (AC only) in the attic

My 1978 Ranch house in Zone 5 (Southern NY) was constructed with the AC Air handler in the attic. He(Heating is gas fired hot water) . I am replacing windows and re-siding - adding 2" of foam to the exterior. There is no good way to move the Air Handler into conditioned space, and I do not want to create a completely unvented attic.

Can I create an insulated unvented "Room" around the Air Handler, and if so, what is the best strategy? And do I remove existing insulation in the ceiling below the Air Handler so "connect" the space to the conditioned interior?
Thanks for any thoughts!

In Energy efficiency and durability | Asked By Mark Rubinsky | Feb 27 14
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