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8 Answers

Triple-glazed windows and passive solar: Does it make sense to install triple glazing on south-facing windows?

I live in Southern British Columbia, so we are primarily heating area. No air conditioning required. We have excellent southern exposure, and large overhangs on south side. We plan to install triple-glazed windows on N. E. and W. walls, but not sure if triple glazing makes sense on the South side. Will triple glazing limit winter solar gain?

In Energy efficiency and durability | Asked By David Slade | May 21 12
0 Answers

Results of window buyer satisfaction survey

BuildingGreen has published the results of its survey asking window purchasers to rate their satisfaction with windows from a wide range of manufacturers.

On the top of the heap were Marvin and Optiwin. Bringing up the rear were Owens Corning Innovision Windows, Paramount Windows, Sorpetaler Windows, Stanek Windows, and Willmar Windows.

The results are published here:
Window and Door Manufacturers: Customer Ratings

In Green products and materials | Asked By Martin Holladay | May 29 12
9 Answers

Basement sub-slab insulation

I should know the answer to this already.... I'm in climate zone 6, using the IRC 2009 code. Table N1102.1 requires R-10 insulation below a slab. I've been taking this to mean under the basement floor, but in re-reading it for the 100th time today, I think I've been misunderstanding the requirement. I know it's best practice to insulate under the poured concrete floor in a full basement, but is it required?

In Building Code Questions | Asked By michael maines | May 23 12
4 Answers

Is 1/8" too small a gap for continuous eave ventilation?

I'm drawing up a small dwelling, and have calculated that I need 1/8" of continuous soffit ventilation under my eaves.
Will 1/8" suck enough air? It seem awful small considering Lstiburek recommends 2" of ventilation between the underside of the roof sheathing, and the top of the insulation baffles.

I've read that continuous venting is preferred, but maybe it's better to go with (4" round) vents between each rafter tail in this case.

Thanks for your help,

In General questions | Asked By Richard Baumgarten | May 28 12
4 Answers

Whole house fan exhaust out my soffit

My Panasonic whisper green is 2 ft from my soffit. Can I run the exhaust through it an down? The roof is vented with 24oc 2x8 rafters.

In General questions | Asked By stephen edge | May 27 12
2 Answers

Happy Memorial Day to all.

One of the recent blogs had me re-reading the October 2010 Cellulose vs fiberglass/mineral debate that went astray (to say the least). The string reminded me how many non-paid hours volunteers put in, along with paid staff hours to keep GBA lively and helpful.

I'd like to say thanks for the passion from the volunteers. The lack of a business interest is what makes this such a legitimate and trusted source.

In General questions | Asked By albert rooks | May 28 12
7 Answers

Curious on what everyone thinks about these fans that claim to remove cooler damp air from finished basements.

The two that I come across are Airtech and Humidex. The "science" behind them doesn't seem to add up for me. Just wondering what others views are on these products.



In Energy efficiency and durability | Asked By terry grube | May 26 12
1 Answer

Proper Cathedral Ceiling Insulation Retrofit with Dense Pack Cellulose

I live in Central VT, the house has a cathedral ceiling, 2x10 rafters, 16" OC, that are currently insulated with R-19 paper faced fiberglass, then plastic vapor barrier and drywall with no boxed off vent channel. There are soffit and ridge vents. My thoughts on a the best cost effective system are as follows:
1) Remove drywall and old insulation
2) Bring down cathedral ceiling by capping it at 8' or 9' with new collar ties
2) Construct 1 or 1.5" air channel with thin panel board, or not, is this needed?

In Energy efficiency and durability | Asked By Andreas John | May 26 12
8 Answers

How do I place baffles for cellulose attic insulation?

I am in zone 5 and have a house with a hip roof and a wide overhang. The house has about 3 inches of rock wool insulation and I would like to add enough cellulose to raise the R value to 60.

The top plate of the side walls is about 12 inches above the attic floor joists. When the rock wool was blown into the attic, apparently in 1961, newspaper was stuffed into the top of the wall cavities to prevent the rock wool from falling down into the wall. There are vents in the soffits at the eaves, outside of the walls.

In Green building techniques | Asked By Gregory Worrel | May 24 12
5 Answers

Air intake for a 70 year old Cape Cod with knee walls

I have a 70 year old Cape Cod with a finished upstairs. A few years ago a steel roof was applied over the existing roof. The contractor put in a ridge vent but I have no air intake. I have 2*4 framing with 1" insulation. What suggestions do you have for getting some air intake into this space ? Gable vents ?

In GBA Pro help | Asked By Brenda Nash | May 25 12
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