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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
7 Answers

Unheated Home Dangers?

In general, what can happen if I leave my home unheated in the winter? Sounds like the green thing to do at first blush... Zone 6. Lots of passive solar windows on the south side of all three floors: Walk out basement, main floor, and attic floor.

The house is well insulated, vented, and dehumidified. Soils are well drained. Basement has 2in of xps on the outside below grade.

Pex lines will be blown out dry before summer shut down.

Thanks, Steve

In General questions | Asked By stephen edge | May 18 12
1 Answer

Rigid foam on the outside - worth it?

I've got quite the opportunity to improve my home's energy efficiency as we need to replace both our siding and our windows which are both original to the house. We had a mild winter here in the northeast this year and our propane usage was way too high. The new windows will be vinyl double pane low-e replacing windows original to the house which were simply popped in without insulation or any regard to energy use. Here are the details of the existing construction, and then some of the struggles I am facing with the different options which are out there.

- 2 story 1800 sqft colonial

In GBA Pro help | Asked By Paul Krsiak | May 24 12
7 Answers

Where do I place vapour barrier in relation to basement slab insulation?

I realize this question has been answered in numerous posts previously; however, our mechanical design involves using Insulworks insulation in the basement. Where and how do you suggest I place the vapour barrier if it is to be added on top of the insulation?

Here's the Insulworks product which involves using staples and is designed for the tubing to snug into grooves. http://www.amcfoam.com/PDFs/Insulworks%20general%20spec_web.pdf

Also, please forgive my ignorance, but why is it important to put the vapour barrier above the insulation and not immediately below it?

In Mechanicals | Asked By Jane Smith | May 23 12
2 Answers

How can I seal DensGlass (exterior drywall)?

I am using DensGlass on the exterior of my home (urban infill lot with zero clearance). I will be wrapping the exterior with Tyvek. I am thinking of sealing the joints of the DensGlass also. Is this overkill? What should I use to seal the DensGlass?

In Energy efficiency and durability | Asked By Charles Eichenlaub | May 23 12
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