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1 Answer

Exterior wall system with brick veneer

We plan to use 8.5" wide plates with a 2x6 wall on the exterior edge and a 2x4 wall on the interior edge, staggered to avoid contact with the 2x6 wall. We will spray 6-6.5" open-cell insulation, use .5" OSB sheathing and a final exterior layer of .5" Tuff R, taped.

We are in Charlotte, so ambient moisture is as much of a concern as thermal. Any thoughts?

Also, is polyiso as effective as extruded polystyrene?


In Energy efficiency and durability | Asked By Tom Dorsett | Apr 10 12
3 Answers

I want to know if I am detailing my thermal envelope correctly

I am building a 3300 sq ft house just north of Phila PA so I considered it as zone 5 just to be safe. From inside to out: 2x6 walls with dense packed cellulose, air sealed with tremco sealant according to GBA strategies. Then plywood sheathing. I'm adding one layer of 1 1/2 polyiso taped and sealed with z flashing all horizontal jts with 1x4 furring strips and vinyl siding. The vented roof will have a raised heel truss of 18 inches for 16 inches of cellulose. I'm following the air tight drywall strategies throughout the house.

In GBA Pro help | Asked By john bell | Apr 10 12
2 Answers

Frost protected shallow foundation retrofit?

I have a ranch with a full basement and attached single car garage in Southern Maine I am about to gut and remodel. The plans dictate that the garage be changed over to a master bedroom/ bathroom. We will be decking over the existing slab which could be removed if necessary. There are a few cracks in the 8" x 4' frost wall and we have determined that there is no footer. The obvious and easy solution was to dig it up and replace it with proper footers and insulation.

In General questions | Asked By Jon Clark | Apr 9 12
6 Answers

How can I "beautify" an almost windowless north-facing house front?

Most passive solar tomes recommend minimizing the size and number of windows in the north facing walls of a house. I'm designing a house that will be on the southwest corner of an intersection. The front door must face north. I can easily eliminate all windows in that wall except for some sidelites by the front door. The inside of the north wall will be mostly closets, bathrooms, and other uses that normally have minimal calls for windows.

In GBA Pro help | Asked By Bill Hoeltgen | Apr 10 12
3 Answers

Will wood siding pass capillary water into wall assembly?

I'm planning to build a low-toxicity cottage. Siding will be unpainted horizontal cedar, on vertical rainscreen furring strips, with an asphalt felt WRB, ADA interior, and insulated with wool or cellulose.

The bottom of the siding will be about 10" from the ground. I'm worried that moisture absorbed by the siding (from rain, or snow melt) will pass through the furring, the sheathing, and into the organic insulation through capillary action.

In Green building techniques | Asked By Richard Baumgarten | Apr 6 12
3 Answers

Plumbing question - Domestic Water Heat Reclaimer

Are these things a good idea? The manufacturer I've spoken with is a nice enough guy but I get the feeling I'm buying a used car.

We've put them into one house and I want to start putting in more, for customs and spec homes. But is it a good idea?

Thanks in advance.

In Green products and materials | Asked By Quinn Parrott | Apr 10 12
11 Answers

Wood Flooring Over Concrete

I'm building my own house, its on a monolithic slab with 2" foam underneath and around the perimeter. My plan was to install strapping and then 3/4 plywood and then hardwood flooring. I was wondering if there were any possible flaws with this design or better approaches.

In General questions | Asked By Mark Hinkley | Mar 13 12
1 Answer

Do You Need to Tape & Seam Seal XPS Over 6 Mil Poly in Basement?

Hi everyone,

I had a question. I live in NJ zone 4. My basement is 4 feet underground and 4 feet above. I am doing an XPS reto install on the interior walls. I put down a 6 mil poly (5 inches up on all walls) and then 2 inches of XPS on the floor and lower walls. I have been using Dow Spray foam inbetween the wall of XPS and the XPS on the floor.

Do I need to seam seal all the joints using Tyvek tape (both wall and floor)? Or does the 6 mill poly below the floor eliminate the need to seam seal?

In General questions | Asked By Dan Nospa | Apr 10 12
4 Answers

Are wood headers insulated with rigid XPS as the filler as structurally sound as those padded out with OSB or plywood?

What about 2x6 walls with 2.5" of XPS in between?

In Green building techniques | Asked By Matt Black | Apr 9 12
6 Answers

Advice for lack of rainscreen or proper flashing

I'm hoping to get some advice regarding my split entry house (circa 1990) in Eastern Canada that has no house wrap, tape or sealant of any kind. Wall assembly is (inside to out) 1/2" GWB, poly v.b., 2x6 studs, 5/8" OSB, 1/2" EPS rigid foam (nailed with roofing nails and no tape anywhere), vinyl siding (no furring). The brickmould for the windows and doors rest against the insulation and are only flashed at the top, tied back to the insulation, not the OSB. I've been replacing windows as needed over the last 5 years and have noticed damage to the OSB and under the windows at each location.

In Energy efficiency and durability | Asked By Darcy Grant | Apr 5 12
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