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

Q & A Instructions

[Click map to enlarge]

The GBAGreenBuildingAdvisor.com web site has a wealth of articles on a wide variety of construction topics. Before posting your question, you may want to check out the articles on this page: How To Do Everything. You just might discover an article there that provides the information you seek.

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

If you want to post a question, 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!

3 Answers

How best to prevent freezing pipes?

I'm working on a (mostly) vacant house near Atlanta. It's on a vented crawlspace and has only electric resistance (baseboard) heat. What combination of heat and dripping water is the least environmentally damaging way to prevent water pipes from freezing this winter?

Asked By Charles Campbell | Nov 22 17
8 Answers

What is a minisplit’s lifespan?

A friend of mine here in Virginia (climate zone 4) heats his 1700 square foot house with a 50 gallon electric resistance hot water heater hooked to radiant coils in his floor. It is a tight, new house with cellulose between 2x6 studs. He generates 90% of the energy he needs for his all-electric house from a 6 kw solar array.

Asked By Timothy Godshall | Nov 20 17
9 Answers

Region 5 below grade basement insulation techniques with intention to finish

I've probably read most or all of the articles on the subject 5-6 times over, but am still left with many questions as the advice can quickly change as the circumstances do, and it's difficult to keep track of all these factors.

My goal is to finish my below grade basement in 18301 Region 5. Cape cod style home built in 1968. 954 sq ft basement.

Asked By Ryan O'Rourke | Nov 19 17
9 Answers

Which gas furnaces are most efficient in their use of electricity?

I am about to replace a 13 year old 120,000BTU furnace with a much smaller unit that will be less noisy.

I understand that the fans of these units are a significant power draw. The state of MA will give the same rebate to all 95%AFUE furnaces. Is there a difference, where some brands of 95% AFUE furnace will actually use a lot less power?

FYI my furnace is in the attic so I will end up putting in a horizontal downflow unit.

Asked By rich cowen | Nov 16 17
5 Answers

Detailing a chimney

I know, I know---if I really wanted to be efficient, I would eliminate the chimney. However, I love a good fire and the warmth from it. So, my new house will have a zero-clearance wood-burning unit (RSF 320).

The chase for the chimney is mostly inside the envelope, except for a portion at the top. I have attached the rendering to show what it looks like from outside.

Asked By Kevin Spellman | Nov 21 17
8 Answers

Insulate a cabin to last

Martin - I've learned a tremendous from you & GBA. This is a 1st asking a question. I'm also an engineer & lic Home Inspector, and I see what happens to homes.
I'm current building a cabin in northern Hayward, WI (Zone 7). I'm on a slab, 20'x26', 1 1/2 story, 2x6 walls 16" OC. I had a local carpenter put up the shell, and the rest is up to me. The cabin is sheathed in OSB, Tyvek, Fascia/soffit, and Anderson windows & door are in. I installed kraft faced R19 Batts in the walls (drywall & siding are not yet installed).

Asked By Dan Musielski | Nov 16 17
6 Answers

Carpet on concrete slab--vapor barrier?

We are working on a :budget restricted" fix-up of a house near Dayton, Ohio (Zone 5). The house is slab-on-grade with solid masonry walls (we are adding 1.5" of polyioso to the interior of them). The floor is concrete slab on grade, and has had asbestos and then vinyl tiles applied to it in the past, and most recently had carpet over this. When I tore out the old carpet it was quite filthy, but I can't say I saw any visible mold, etc. on the surface or backing.
Approximately 75% of the slab is covered with these tiles, and the rest has various amounts of mastic or glue.

Asked By Mark Waldron | Nov 20 17
3 Answers

Is exterior wood paneling on cob possible?


My partner and I are located in France. I grew up in Maine and became found of farm houses. We are planning on building a cob house for cost efficiency; however, a few years down the line, I am curious if it is possible to add wood siding to the exterior of the cob later on? Again, I'm very found of the farm house look. Any suggestions or advice? Much appreciated. Merci beaucoup.

Asked By BP8963 | Nov 21 17
6 Answers

Chimney chase condensation

Hello All,
Classic problem I believe.

I have a wood framed chimney chase which houses two 8" insulated, stainless steel metalbestos wood stove pipes and my main DWV stack. On certain days, when the inside/ outside temps, and the relative humidity are just right, I have condensation build-up and dripping from the underside of my chimney chase roof.
Construction detail:

6x10 timber rafters 36" (on center)
2 x 6 rough sawn decking (not T&G)
Grace Tri-Flex
3 layers of 3" Polyiso foam board
2x6 Sleepers 36" (on center, screwed to rafters below)
3/4" T&G OSB decking

Asked By Dave Cummings | Feb 16 12
7 Answers

Attic fan for ventilation in winter?

I have ice buildup because of heat escaping and melting snow and causing ice buildup on my gutters. I have vented gables on both ends of my attic in a split foyer home. Can I install of ventilation fan and set the temperature at say 40 degrees to move that warmer air out and avoid the ice buildup??
Any advice is greatly appreciated... Mike F

Asked By Feiks | Nov 20 17
Register for a free account and join the conversation

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