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0 Answers

Dow SIS panel lives on....

I'm posting a letter from Dow Building Solutions, showing the manufacturing continuation of the Dow SIS panel. Read on…

In General questions | Asked By Armando Cobo | Jul 21 12
8 Answers

SIPs vs. spray foam on exterior walls to air-seal my building envelope.

I am having a new home built. I was planning on using spray foam insulation and want to air seal my building envelope. Will the use of SIPs in place of standard stud walls and spray foam in those walls air seal my home just as well?

In Energy efficiency and durability | Asked By Eric Wallace | Jul 20 12
5 Answers

Selecting and installing a standing-seam metal roof

Are there any disadvantages to installing a metal roof over a single layer asphalt roof? The cost savings of removing the old roof and disposal make this option attractive.

Also, does the heavier 24 gauge metal roof have advantages over a 26 gauge roof? I've heard from other contractors that the heavier gauge is harder to work with and the finish cracks more easily.

In Green products and materials | Asked By Bill Tine | Jul 17 12
4 Answers

Solution for can lights in cathedral ceiling

Our Colorado home has a two story cathedral ceiling with several can lights. The house was built in 1987 when the building codes were not nearly as stringent as they are now. We had a blower test done and realize that we need to try to seal them. We don't have an "attic side", so cannot build an insulated box around them. The earlier discussions indicated that the baffles would help a little, but not make a significant difference. So..., I know that I wouldn't install recessing lighting in new construction, but what can I do to improve my existing situation?

In Energy efficiency and durability | Asked By Nancy Andrews | Jul 20 12
2 Answers

Is silicone caulk appropriate for wood-to-wood connections?

I'm planning to go with the airtight drywall approach, and am looking for a product to seal some of the wood connections...especially in my window jambs.
Silicone sounds relatively non-toxic, but have read that it doesn't adhere well to wood. Is that critical?

It seems to have a very long rubbery lifetime. Even without good adhesion, wouldn't it behave like a gasket of sorts?

In Green products and materials | Asked By Richard Baumgarten | Jul 19 12
3 Answers

New Home Build (Zone 6)

We are planning a new build next spring in zone 6 --Ottawa, Ontario, Canada

2 questions:

1. Structure --can I use rigid foam insulation (in place of OSB or plywood for exterior sheathing?) with corner bracing and in conjunction with fibre cement board and some sort of rainscreen (to create drainage)

Frame > Rigid Foam Insulation > Rainscreen > vertical furring strips > fibre cement board

Will this be strong enough structurally to hold up the fibre cement boards?

2. Insulation on this house (as mentioned zone 6)

In Green building techniques | Asked By Stephane Vizzari | Jul 19 12
8 Answers

The "First $25K"

I've heard y'all talk about "the last $10000," referring to the materials and design choices you would make if you wanted to upgrade a house design and has $10K. My question is a little different -- at long last I'm buying a house and I've reserved $25000 (+ 10% snafu reserves) to improve the building's performance and durability.

If you were me, where would you put that $25000 in this house:

In GBA Pro help | Asked By JoeW N GA Zone 3A | Jul 19 12
3 Answers

Factory-adhered polyiso/OSB over rafters

A number of products are on the market that consist of polyiso foam insulation adhered to OSB. The manufacturing process looks to be one of the foam being sprayed directly on the OSB with no glues involved. Can this product be laid down on top of the rafters and screwed in place? Or is it required to have an OSB or plywood deck first?

i.e.: Drywall, rafters with cavity insulation, Hailgard, roofing paper, standing-seam metal panels

In Green building techniques | Asked By Arthur Dorrit | Jul 13 12
4 Answers

Do I use flashing or what?

I have a plywood exterior wall and plan on adding house wrap with built in drainage plane, one inch foam board. If I put 1x4 furring strips on the foam what do I use to keep bugs from crawling up the air gap between the foam and the siding?

In General questions | Asked By Tim Stumpf | Jul 19 12
6 Answers

Concrete Cracks when using sub-slab insulation

On a number of projects we seem to encounter problems when pouring concrete slabs over thick rigid insulation. The insulation seems to interfere with the curing process and we get surface cracks that are problematic when using the concrete as the final finish surface. The concrete that is being poured in unconditioned spaces (like a garage) at the some time do show any cracking even though they were the same mix and poured at the same time. Has anyone found a strategy that might lead to better results?

In Green building techniques | Asked By Ron Flax | Jul 19 12
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