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2 Answers

We're building a pretty good green home in Gardnerville, NV, a place that gets 8" rain per year. We get cold in the winter (-10°) and are pretty warm in summer, about 10 days with >100° temps. Radon is an issue in our area. Our new home is being constructed with SIPs, therefore no attic space. We have natural gas at the site, pretty cheap in Northern NV. Our plan is forced air heating via Natural Gas in winter and a few days in summer when we'll use A/C.

Asked By Richard Starrett | Apr 18 14
4 Answers

I have a 1971Lancer double wide mobile home with hardboard exterior walls that seem to be toxic. I am sensitized to chemicals due to chronic pain and fatigue. The hardboard has a strong petrochemical aroma when the sun heats it; or when i open up the wall space, such as when working on an 120v wall box. I have been around all the other house components before (vinyl, paint, carpeting, MDF, etc) and have finally realized its the hardboard that is the main culprit.

Asked By Joe Tichenor | Apr 18 14
6 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
1 Answer

I have a radiant floor that was installed under my kitchen floor using the aluminium heat transfer plates. Below the kitchen is a semi finished, semi conditioned basement. I would like to insulate the floor to allow as much of the heat from the pex tubing to translate to the floor (rather than helping heat the basement). Is a radiant barrier (foil) with an airspace beneficial? does the insulation need to be installed airtight? Is fiberglass a good choice in this application? Any insight is appreciated!

Asked By Pete Marthaler - Zone 7 | Apr 18 14
2 Answers

In an answer to a recent question I had, Martin Holladay indicated that he has concerns about AirKrete shrinking and crumbling. According to the website and company representatives, AirKrete has 0% shrinkage and the formulation has been changed to alleviate the friability concerns.

I'm interested to know if anyone here has used AirKrete and, if so, what your experiences are with it.

Thanks in advance!

Asked By Stacey Owens | Apr 15 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
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
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