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10 Answers

Have a cathedral ceilinged residence with 4x6 tong & groove hemlock exposed to the interior supported by gluam arches at 15' on center. Want to reshingle this uninsulated roof with thick nailable rigid insulation on top of the woo deck.

Is there a guide for determining insulation thickness and selecting a vented or non-vented system? Have gotten very mixed answers from architects and engineers, and the manufactures of the systems are of little help. Since non-vented is the leastexpensive, it could offer a better payback. Am in 5,500 degree day climate in New York. - Thanks, Rob

In Green products and materials | Asked By Robert Damico | Oct 7 11
7 Answers

Just watched the video regarding vented attics and insulation.

We are re-purposing a 40 year old mill building. (Norfolk, Ct 06058, the icebox of CT). Radiant heat in finished concrete floors is in, German Shucco windows installed. We have a new standing metal seam roof, done. There are sofit vents on both sides, all along the gutter line, ridge vent entire length of roof, as well as 2 gable vents. We have already sprayed soy foam in the walls, 5.5 inches (closed cell). The HVAC trunks are installed just above the proposed drop ceiling.

In Energy efficiency and durability | Asked By gary scheft | Oct 12 11
5 Answers

I work in Zone 4a and would like to know if it would be a problem to put Tyvek over OSB sheathing and then cover the Tyvek with one inch XPS foam.

In GBA Pro help | Asked By Mike O'Keefe | Oct 11 11
2 Answers

Question for Martin Holladay,

We are removing spray foam insulation from our attic that has started off-gassing after 5 years (installed when house built). The recommended replacement will be as follows:

change attic space from unvented to vented with install of ridge vent and removal of soffit blocking

In GBA Pro help | Asked By Jas Thurber | Oct 11 11
1 Answer

I just moved to the Verde Valley of AZ from the deserts. This is my first home that is not on a slab foundation. The home is sitting on a slump block foundation raised about 3 feet above the ground.
There are 3 vents in the exterior foundation. Should I block those off in the winter? And if so, when?
What time of year should I reopen them?


In Energy efficiency and durability | Asked By Richard Louis | Oct 11 11
1 Answer

Pacific Northwest Region-Washington
Attic space over living space has loose fill fiberglass/no vapor barrier and is vented (double bird-hole eave intake vents and continuous ridge vent exhaust). Garage is sheet-rocked but attic space over attached garage is not insulated. Attic access is in garage ceiling.
Moisture problem evident on underside of roof sheathing. More apparent over living space than garage.
Plan to seal gaps and add insulation but curious about separating garage attic space.

In Energy efficiency and durability | Asked By James Cavallaro | Oct 11 11
4 Answers

My new to me home has a solar heating set up under the floor, that vents directly into the crawl space. (3 ft tall)
When the blower turns on, the air in the crawlspace is pushed up through vents in the floor. There is no ductwork connecting the vents to the blower fan. This seems a little bizarre to me, but maybe that is how the system was designed? I don't know when it was installed, but the house was built in '78, and the solar tank is under the house, along with the water heater.

In Energy efficiency and durability | Asked By Richard Louis | Oct 11 11
7 Answers

I recently erected a red iron framed steel building with 26 gauge steel panels on the exterior walls. During the planning stages, I was going to apply closed cell foam. Unfortunately, I am no longer able to afford this option. I am now looking at using fiberglass batts. My plans are to stick frame the interior walls with standard wood 2x4 studs. This will create a 12" deep wall cavity in which to insulate. My thought is to install batts of EcoTouch R30 in the steel wall cavity and R13 in the 2x4 stud interior walls. This will yield R43 in my walls.

In Energy efficiency and durability | Asked By Dwayne Cormier | Oct 6 11
1 Answer

I am re-roofing a cathedral ceiling house. Looking up it has 2" tongue/grove pine resting on 4x6 joist beams (5') centers running to a ridge beam. I have done the tear off - and the 2" pine is the ceiling on the bottom side and existing decking on the top side. The pine is the only thing up there now. It's a tight fit. 3/12 pitch - Southern Michigan.
I want to insulate, ventilate if necessary, and re-roof.
What materials should I use?
What is the order of the layers needed?
Can I lay down a layer of roofing paper on the top of the pine to protect it while I make the decisions

In General questions | Asked By craig askins | Oct 11 11
1 Answer

There are a couple of comments that stick with me regarding XPS efficacy over the long haul:
1. A contractor uncovered foam insulation he had installed approximately 10-15 years ago on a house. He found gaps between the foam panels due to shrinkage over time.
2. Martin Holladay interviewed a representative from a major XPS manufacturer who said they were constantly reformulating their XPS products which could mean further unforeseen problems.
The questions that arise from these comments:

In Energy efficiency and durability | Asked By HORST SCHMIDT | Oct 11 11
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