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3 Answers

PV shingles?

I have a client who is interested in PV shingles. Not sure why, but I told him I'd look into it. Has anyone used any product recently? Pros & cons? The obvious con seems to be repairs and damage.

In Green products and materials | Asked By Dan Kolbert | Apr 13 12
5 Answers

Alternatives to Exterior Foam

I am building a new house in Vancouver, BC. From what I have been able to determine, exterior foam or rockwool would require an envelope consultant to satisfy inspectors, with numerous costly inspections to the tune of about $3-5K. With fairly significant glazing am I better served to go to triple glazed windows (u=.17) for north facing windows, possibly furr 2x6 walls in with 1.5 " foam/1/2" wood to reduce thermal bridging and increase cavity insulation with dense packed cellulose insulation?

In Green building techniques | Asked By paul preto | Apr 13 12
0 Answers

Michigan based architect/builder referral

to design &/or build the PGH in Suttons Bay---north of Traverse City. We have researched passivhaus and have decided the expense is too high for the energy savings payback. We do like the idea of the Pretty Good House! Do-able with our budget.


In GBA Pro help | Asked By jim white | Apr 13 12
4 Answers

Open vs closed cell cavity insulation with exterior foam panels?

Hello all,

We are debating whether open or closed cell is the optimal cavity insulation for our wall assembly.

The wall assembly (inside to out) is as follows:
- 2x6 conventional framing
- Water-resistive sheathing (Zip System), taped at all joints.
- Foil-faced polyiso insulation panels (2" thick), taped at all joints and edges.
- 3/4" vented rainscreen.
- Pre-primed/stained cedar siding.

In Green building techniques | Asked By Jonathan Jacobsen | Apr 12 12
10 Answers

We have about 13 inches of 3-wythe brick load-bearing walls

We are not doing any insulation on the brick walls, but are having issues with the building inspector coming up with a framing plan. We live in MN. We have fought the city and won a battle so that we do not have to insulate because of the fears of the failure of our brick because of the freeze thaw cycle here.

In Energy efficiency and durability | Asked By Kristina Beedle | Apr 10 12
1 Answer

Thermal break at curtain wall window

Working on a large project....climate zone 6 with 7600 HDD.....
We have an aluminum curtain wall assembly that is hung off of the steel super structure with clips. The not glass faces are covered with a 1/2" aluminum plate rain screen attached to hat channels. To close the curtain wall jamb off, the plate extends out past the curtain wall frame. So the 1/2" alum plate, which is fully exposed to the exterior, is in full contact with the curtain wall frame jamb which is 10" deep (so 10" of exterior contact).

In Energy efficiency and durability | Asked By Jesse Lizer | Apr 12 12
1 Answer

Need a "reference house" energy use estimate (Utah - 7000 HDD/200CDD)

Does anyone have a link for a website where I can get estimated energy use for the RESnet "reference House" built to IBC 2006. We want to validate the HERS index (24) on our new house, and now have one year of data to compare it to.

In Energy efficiency and durability | Asked By Richard and Miranda Menzies | Apr 11 12
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
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