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4 Answers

Cold Climate - New Construction

I've been reading in this site for about 3-4 weeks now and it has been a great resource.

Most of the homes discussed are warmer weather climates

I live in Northern Ontario (Canada) and will be building a new house in the spring. My building inspector in my area says it's a zone 2, but that does not tie into what I have been reading here. I consider it to be cold weather climate as we are about 4 hours drive north of Toronto.

In Energy efficiency and durability | Asked By Brian Krmpotic | Dec 15 11
1 Answer

Open-cell or closed-cell SPF in 2x4 walls?

I am building a house (or rather my builder is, I am a semi-well read novice, not an expert at all) in Climate zone 4 in the western piedmont (near the foothills) of NC. We have relatively hot periods in the summer (several weeks of 90 deg +), and we have several weeks of below freezing temps in the winter. This is definitely a "Mixed" climate.

In Energy efficiency and durability | Asked By Patrick Steagall | Dec 15 11
5 Answers

Sleepers below rigid over garage?

I'm looking at the GBA details for insulated floors above garages and see that both use sleepers between the rigid foam under the floor trusses and the drywall ceiling.

Why not just attach the drywall through the foam? Any differences in the way you would do the assembly for an attic truss instead of the floor trusses shown?


In Energy efficiency and durability | Asked By Hallie Bowie | Dec 14 11
11 Answers

Floating plywood floor on rigid foam insulation on concrete?

I am proposing a project for a slab on grade Habitat house with 2" of foam under the slab and 1 1/2" or 2" of foam on top of the slab with 3/4" t&g plywood or osb floor. I want to float the plywood rather than use screeds to minimize thermal bridges. The interior walls are all non-bearing so they can be fastened to the plywood. I am certain that this is not an original idea so I would like to know if anyone has tried this and what the down side issues might be.

In GBA Pro help | Asked By Philip Koepf | Dec 14 11
5 Answers

Insulation of timber suspended floor in basement

Hello all,

In Green products and materials | Asked By T Vermont | Dec 14 11
5 Answers

Last winter I ordered window inserts

Last winter I ordered window inserts to beef up my double-pane, double-hung windows and I think the results were good. In the late spring I also installed double honeycomb cellular shades to abate summer heat (inserts in storage at this point).

The window inserts I use are from [insert name of company here]. They come with a heavy gauge film mounted on a frame and a foam gasket around the frame for fitting and airsealing. Essentially, they are seamless interior storm windows. The insulating shades are a close fit within the window frame.

In Energy efficiency and durability | Asked By Christopher Ring | Dec 14 11
6 Answers

Insulated roof question

I have a cape and have torn off the roof, added eaves and overhangs, moved the thermal boundary from the knee-walls to the gable walls and now am tweaking my approach on the roof/rafter bays.

In Energy efficiency and durability | Asked By Robert Post S.E. Pennsylvania Zone 4a | Dec 14 11
8 Answers

Does glass thickness affect VT and SHGC?


I've ordered a fixed triple glazed window through the person who will be installing it, and it has finally arrived. However, the size that has arrived is not the size I ordered (in writing).

In addition to the issue of whether or not it'll fit into the RO, there's the other issue, that at widths greater than 55" (I'd ordered 55") the thickness changes from 3mm to 4mm (I think I have that right).

In General questions | Asked By Minneapolis Disaster, 6B | Dec 13 11
1 Answer

Musings of an energy nerd

I think that Martin should put his musings into a printed form...it would make a handy reference book. Who else here would support this idea?

In General questions | Asked By Garth Sproule 7A | Dec 13 11
4 Answers

I'd like to insulate the floor of my attic with spray foam. How do I know what type of foam to use?

I live in Iowa and my attic insulation requirement is R-49. I currently do not have enough insulation and I'd like to take it up. I have been told to use fiberglass or cellulose depending on who I'm talking to. I'd prefer to use cellulose, but I have concerns about too much weight on the ceiling that would cause it to sag. I would like to foam the floor of the attic and put blown-in cellulose over top. I think this would provide the best air sealing and insulation performance. I'm confused about what type of foam to use.

In General questions | Asked By Jason Schaffer | Dec 13 11
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