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8 Answers

Looking for help on a wall system

We are building north of Ottawa, which is zone 6a (I think). Pretty chilly in the winter. We have been given a good quote to frame up our house with typical 2x6 framing, so would like to go ahead with it. The wall system we are thinking of for insulation would be, from outside to inside:

Wood siding
Tyvek over Plywood sheating (taped, sealed)
cellulose or roxul in a 12 inch space
tyvek (taped and sealed)

In Energy efficiency and durability | Asked By jessie pratt | Oct 8 12
5 Answers

What is N-factor?

I was asked by a client -- I'm an Energy Advisor -- what the N factor was for his town requirements, and I didn't know the answer.

In GBA Pro help | Asked By Roland Schoenke | Oct 10 12
2 Answers

Polyiso insulation outside -- what goes inside?

2x4 walls covered with sheathing, housewrap (taped), 4 inches of foil faced isofoam board, strapped with wood siding. All gaps in foam board are spray foamed and the window/door openings are sealed and flashed properly.

Plan to fill inside cavity with 3" of closed cell spray foam with drywall covering, no vapor barrier. House is in zone 3, cold northeast valley.

After reading many ideas and/or opinions on the subject of moisture in walls I'm not sure if this is a good idea. Any better solutions or will this work?

In General questions | Asked By darren williams | Oct 8 12
2 Answers

What is best to insulate with over existing blown in fiberglass insulation?

I have about 9inches of blown in fiberglass already and would like to add more.

In General questions | Asked By Gerard Timm | Oct 9 12
2 Answers

Insulation above a t-bar suspended ceiling?

Create an insulated office within a larger warehouse space. Warehouse is 18' floor to roof deck, clients want 10' t-bar ceiling for new office space.

Issue: how to insulate...
Existing building is poorly insulated, thus need to create insulated ceiling above office.

Thus far, ideas include installing Owens Corning Sonobatt directly over the t-bar ceiling.

In Energy efficiency and durability | Asked By Kyle England | Oct 9 12
3 Answers

Storm Windows - Worth the Investment?

I live in a historic district in Washington, DC where storms windows are regularly suggested as ways to save energy where single pane windows are common.

The only way that I can theorize that storm windows could be worth the investment would be if they were air tight and at some orientations, low-E coated.

Unfortunately, most of the storm windows that I see have large gaps, deteriorated weather stripping and lack low-E coatings.

I feel like storm windows are like fiberglass insulation, theoretically a good idea, but in practice never installed properly.

In Energy efficiency and durability | Asked By Cliff kornegay | Oct 3 12
10 Answers

Conflicting HVAC Quotes

The original design for my house was 1900 sq ft 1st floor (front faces due North). with a 1900 sq foot finished basement. 450 sq ft attached garage. It is a walkout that faces due West. Only the walkout wall is fully exposed (and will be covered with slate). Remaining basement wall exposure is 12" at the top (also slate covered). First floor and basement ceilings were to be 9'. Using Marvin Integrity fiberglass windows with LoE2 coating for North & South facing windows. LoE3 for East and West facing windows (only 1 5x5 facing East, and one 5x5 and one 2.5x5 facing West).

In General questions | Asked By Will Norris | Oct 4 12
6 Answers

Vent caps sans duct?

Does anyone know of a vent cap manufacturer that makes vent caps without a piece of duct already pre-attached?

I've got a "Heartland" vent cap for the dryer exhaust which works the way I'd like the rest of my caps to work - it installs over an existing piece of duct that protrudes from the wall.

I have looked at a few caps that don't have duct attached but they were all cheap p.o.s...

In Green products and materials | Asked By Lucas Durand - 7A | Oct 5 12
6 Answers

Passive House Consultant training

I'm considering taking the Passive House Consultant training program, and was curious if anyone out there has done it. I'm a LEED AP (BD+C, Homes) and a licensed architect with over 17 years of experience. I'm doing a lot of reading about the standard (the many articles and posts on GBA have been very helpful, thanks), but haven't seen much on the consultant training. Any opinions?

In PassivHaus | Asked By Roxanne Button | May 5 10
2 Answers

Cold climate vapor barrier

I live in Alaska. Do I need to have a poly vapor barrier to meet code requirements?

In Building Code Questions | Asked By michael o'Laire | Oct 8 12
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