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9 Answers

Looking for low cost and novel way to form concrete footers

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?

In General questions | Asked By Chuck Jensen | Apr 15 14
3 Answers

To condition (the attic) or not to condition, that is the question!

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.

In Green building techniques | Asked By Stacey Owens | Apr 15 14
1 Answer

Windows and Exterior Rigid Foam

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?

In Green building techniques | Asked By Matt Cibula | Apr 16 14
1 Answer

EPS & SIPs

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?

In Green products and materials | Asked By Peter L | Apr 16 14
6 Answers

PassivHaus barndominium in Minnesota

Hello everybody. First post -- just signed up. Great site. I live 30 minutes north of the Twin Cities and I'm looking at building a passiv type haus. I've found the land I'm building on (10 acres) and have somewhat of a plan for the building.

My wife and I want to build a barndominium. Looking at 50x70 total with 30x50 two stories and 40x50 shop. I have a general idea of how I want to build but alas I am newb and was hoping for some insight with the pros on this site.

Thanks again and any advice would be greatly appreciated.

In PassivHaus | Asked By Ryan Picha | Apr 1 14
23 Answers

IF Not .... Then Why Not ?

How about an affordable not-so-big house?
3 Bedroom 2 bath ....1,400 sf.....
One DUCTLESS Mini-split
and a thoughtfully DESIGNED ventilation "system"....

With properly 'tuned' enclosure design and "tuned" windows......
Could it be made to "work" (satisfy 90% of occupants) ?
in San Diego?
in Seatle?
in Boston?
in Fargo?
in Dallas?

If Not ..... Why Not?

In Energy efficiency and durability | Asked By John Brooks | Apr 11 14
4 Answers

Usonian house restoration - sunroom window replacement (direct set double pane or single pane)

Hi,

We are currently restoring a Usonian style house built in 1962 here in Northern Illinois. The sunroom is currently being restored to its original design with a few exceptions:

In GBA Pro help | Asked By Ryland Bouchard | Apr 13 14
6 Answers

When is an ERV needed?

How tight does a house need to be at ACH 50, before an ERV or HRV is recommended?

In Energy efficiency and durability | Asked By Allen Brown | Apr 12 14
10 Answers

ERV or HRV with these humidity numbers? Also best HRV brand?

I have a humidistat sitting in my house the last few years, and have taken notice of the RH%.

I am concerned that an HRV will dry out my house too much. Location is Toronto which has cold winters (down to -18 celcius) and summers up to 30 and 35 celcius humid

With a forced air system with a humidifier installed, we go down to about 16% humidity in the winter on the coldest days. typical is around 20%-24% . In the summer we are at about 50-54% ish.

with these numbers would an HRV make it too dry, or would the numbers typically be affected only slightly?

In Mechanicals | Asked By cory b | Apr 13 14
3 Answers

XPS or EPS?

My builder is going to use 5 inches of EPS rather than 4 inches of XPS on the exterior walls. His reasoning is the same insulation value for a little less money ....any pro's or con's either way?
Thanks,
Bob

In Energy efficiency and durability | Asked By bob holodinsky | Apr 15 14
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