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7 Answers

Ideal roof overhang length?

I think I have decided on the wall assembly that I want to use but by the sounds of it it spend time concentrating on the wall but very little time on the roof.

I have read several books on sustainable design and affordable or low tax housing. My general plan was to build a rectangular house with a gable end roof on a 4/12 pitch. I had intended to use either a 16” or 24” raised heel truss with 2’ overhangs. I intended to use through fastened metal roofing. My design goals are one and only one roof line.

In General questions | Asked By Shane Fairman | Nov 30 12
2 Answers

Amercian clay and water (wall plans)

We're in Austin TX (Zone 2). The house has decent eves (3') but lots of high gables. Our climate is mostly dry, but with some humid periods and rain comes in large, sometimes driving, storms.

Our current wall profile (probably 50 years old) and, from inside -> out:

Concrete block (8") -> Stucco (very, very hard) -> Paint (lead based).

We have some newer sections with just concrete block, parged with Type S, unpainted. These were windows we made smaller.

Eventually we want this profile:

In Plans Review | Asked By James Howison | Nov 30 12
1 Answer

Tempering water for domestic hot water

HI, I’m looking to build an Insulated Raft or Frost Protected Shallow Foundation single story in zone 6. I have a few questions regarding waste water heat recovery and tempering incoming cold water for domestic hot water.

I am interested in a grey water heat recovery but since i’m not planning to build a basement so I can’t install the standard vertical mount heat exchanger.

In Mechanicals | Asked By Shane Fairman | Nov 30 12
4 Answers

When Alan Met Sharon (A U-value Romance) - YouTube Video

http://www.youtube.com/watch?v=_xro2FPaRf8&feature=youtu.be

I question the use of marshmallow insulation in this wall section, though. Too many voids. I probably would have used sprayed-in cheez-wiz.

In General questions | Asked By John Semmelhack | Nov 30 12
5 Answers

Post Hurricane Sandy repairs: advice needed

Insulate new ducts? Bubble wrap or what kind? Water in crawl space solutions?

Hi, I have a small cape cod house on a lake, 2 blocks from the ocean in NJ, that was recently flooded by Hurricane Sandy. The seawater came 4' above ground level, 14" into the house.

There is a low dirt bottom crawlspace, which has water or is wet most of the time because the water table is so high.

In General questions | Asked By Sandy Sole | Nov 30 12
2 Answers

How do I get an R-20 wood wall?

Insulation method to get R-20 in a 2x4 framed wood stud wall?

In Green building techniques | Asked By Diego Gutierrez | Nov 30 12
5 Answers

Potential problems regarding the use of ZIP System's new R-sheathing?

Does anyone see any potential problems using ZIP System's new R-Sheathing? The product comes in either 1/2" or 1" polyiso on the back of the sheathing between the sheathing and the studs. http://www.zipsystem.com/zip-system/rsheat.aspx.

Once again I am trying to figure out less costly ways to combat thermal bridging, create an air seal, and provide a rainscreen. I would be using the product with no interior vapor barrier therefore reducing the possibility for trapping moisture in the wall cavity.

In GBA Pro help | Asked By Jason Macdonald | Aug 1 12
10 Answers

Bubble wrap window insulation testing

I have a large amount of glass in my 1965 home. I had read a question here that talked about window quilts and that eventually led me to the idea of covering windows with bubble wrap.

Much of my glass including large sliding doors etc are all bare aluminum frames without thermal breaks or insulation. The idea of adding a semi-clear covering that admits light and I can apply over the glass and frame is pretty appealing.

Of course replacing the windows is a huge expense. Some have single pane and others are double pane from 1965.

In General questions | Asked By Mark Renfrow | Feb 9 11
6 Answers

Can I spray closed-cell insulation on inside of brick wall ?

I live in South Louisiana and am remodeling a Ranch Style Brick Home. I have removed the drywall and have 2 x 4 studs, 1/2 " impregnated sheathing, 2 1/4 " dead space then brick and mortar.

If I remove the 1/2" sheathing from the inside (easy to cut out) , this would give me 6 1/4 " space to insulate. Could I spray the closed cell spray foam directly aganist the inside brick wall filling the wall cavity up to edge of 2 x 4 , then finish with new drywall? Would this create any future problems for walls?

In Green products and materials | Asked By Theresa Aguillard | Nov 27 12
3 Answers

Recessed lights/speaker caps

The family that lived in my house previous to mine were music lovers. As a result, they installed two 8" ceiling speakers in every room of the house, including the baths! Now, in addition to the 26 chimneys commonly called recessed lights that penetrate my ceilings, I also have 24 chimneys that produce music while they leak!

In Energy efficiency and durability | Asked By Chris Brown | Nov 29 12
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