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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
2 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
10 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
10 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
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
1 Answer

I am installing new windows and cement board siding. We are adding an inch of foam board to the exterior. I know the siding can be nailed through the foam board into the sheathing by extending the length of the fastener, but can the same be said about nailing the window (flange) through the foam board? I realize that I have either that option or the option of building out my frame by an inch with OSB or ply so that I get a solid nailing surface. Is there a preference?

Asked By Matt Cibula | Apr 16 14
1 Answer

Since a SIP is basically like an I-beam type of setup, it relies heavily on the EPS foam core for its strength. The downside is that EPS begins to melt around 165F - 180F. Once the foam fails, the structure fails/collapses.

Has anyone observed or read about a SIP roof or SIP wall home being involved in a fire? If so, what was the outcome?

What's the hottest temperature that a SIP roof can get? I assume in the desert southwest a SIP with a metal roof on top can see some high temps. Is it hot enough to melt the EPS core?

Asked By Peter L | Apr 16 14
1 Answer

Thanks for any suggesWhat is a good old bathroom exterior wall progression method (1947 home in Edmonton, Alberta) ?

From outside to inside: cedar siding, then 2X6 Douglas Fir planks, 12" studs.

What would be a good insulation choice?

What would be a good baker board choice?

What would be a good drywall choice?

Should a vapor barrier be used?

Will also be installing a bathroom fan- horizontal exhausting through exterior wall due to possible vermiculite/asbestos in attic. What would be the specs for this? It is difficult to find information for this unusual location.

Asked By Lisa MArtin | Apr 15 14
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