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26 Answers

Hi,
I live in Massachusetts (Zone 5A) and have some space over the garage that I would like to finish as an office. The space has a sloped roof with 2x8 rafters, with soffit vents and a ridge vent (but no existing insulation). I'll be adding some 5 foot kneewalls and a ceiling, leaving about 4-5 feet of cathedral ceiling between the two.

What are my options for insulating the space? I have looked at closed cell insulation but quotes have come in at about $5-6K to insulate the entire roof deck (no venting). So I'm looking for cheaper alternatives.

I am thinking this (outside in):

Asked By Andrew K | Oct 4 13
1 Answer

I have a recurring question / situation that comes up in my east central MN location (6b-7a border). There are many 1970's homes undergoing remodeling and looking to add insulation for improved comfort and energy effciency. Miost common construction is drywall, kraft faced R13, 2x4 walls, 3/4" Bildrite (asphalt fiberboard sheathing).

Asked By Troy Tvedt | Apr 17 14
5 Answers

We are finishing a space above our garage, about 26 x 26', to make a studio, and are trying to keep costs down and still insulate it well. Is the difference in price between the two types justified in improved insulating quality over time or is the actual insulation pretty comparable? The cellulose people are adamant about their product, and the fiberglass people say the difference is negligible. And then how much more/less green are the two? Thank you!

Asked By Patricia Basha | Apr 17 14
3 Answers

Hey guys, what are your experiences with putting a 100 psi polystyrene under a footing to help eliminate as much thermal bridging as possible? This is for a residential setting. It would be in the center of the house the load of the first and second floor and possibly the roof would be on it.
Can anyone recommend a engineer that may have experience in this?
Thanks.

Asked By Kirk Nygren | Apr 16 14
15 Answers

In another thread, my choice for HVAC was appropriately questioned. The system seems inordinately complex, costly, and convoluted. At least, on the surface. But digging deeper, the reasoning behind the design becomes clear. But, does that make it right? Is this the best HVAC design, or is it redundant and wasteful?

Here are the pertinents:
• Climate Zone 6
• 2700 sq. ft. finished space in story-and-a-half (bungalow style) house
• 2000 sq. ft. unfinished basement (future completion for aging parents)
• 4 Bdrm, 3 ½ bath house
• Tight, highly insulated home

Asked By Kent Jeffery | Apr 16 14
11 Answers

So, I’ve been researching the proverbial pee-pee out of this question: dedicated ductwork for my HRV or simplified installation? Here are the pertinents:
• Climate Zone 6
• 2700 sq. ft. story-and-a-half house, along with a 2000 sq. ft. unfinished basement
• 4 Bdrm, 3 ½ bath house
• Double stud walls, spray foamed exterior sheathing and cathedral ceiling, very “tight” and efficient house planned.
• Geothermal ground source heat pump, with gas furnace back-up (Xcel Energy “dual fuel” program allowing electricity to be purchased at 40% rate for geo.)

Asked By Kent Jeffery | Apr 15 14
1 Answer

For anyone who naturally performs THERM calculations in their head, the answer would be intuitively obvious, but to know for sure I'd have to stop and learn THERM (which wouldn't be a bad idea).

Before I build this, would it be better to place to layers of vertical 2" EPS on the outside, maybe 32" and 16" deep, to reduce what looks like an excessive thermal bridge right at the top of the foundation?
Cross section:

Asked By Chuck Jensen | Apr 16 14
9 Answers

I am using ICFs to form a foundation stemwall and am pondering different ways to form a 16" x 8" footer that doesn't require a ship load of 2 x 8 or 2 x 10. I can't form it using the trench walls because county code requires 38" w x 12" deep compacted structural fill below the footer for my soil type. My thought is to use ripped plywood with some kind of wire or snap tie and 2x4 strongback with some fill holding the bottom in. If using plywood, what is a good sealer to use for saving and further ripping the plywood to use as furring strips for siding? Any cool cheap ways to form footers?

Asked By Chuck Jensen | Apr 15 14
3 Answers

After reading and reading and reading (including lots of GBA articles), I thought that I had this figured out. Our plan was to have a non-conditioned attic space, with continuous soffit ventilation along with ridge vents. After further reading, especially Dr. Joe's Top 10 List of Dumb Things to do in the South, I am confused. Please share whether you would vent an attic or not with the following considerations in mind:

- located in western North Carolina, zone 4, mixed humid
- one level, slab on grade home, approximately 2100 sq. ft.

Asked By Stacey Owens | Apr 15 14
4 Answers

Ok, I am going to thoroughly expose my lack of knowledge with this question (no claims to any expertise on my part), but I'm hoping that some of the experts here can comment on something I am thinking about.

Asked By Stephen Youngquist | Apr 16 14
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