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7 Answers

Add insulation to dormer attic?


I need some more advice. I live in North Alabama -- climate zone 3. Most of our home is a built up cathedral roof system. However, we have 2 gabled dormers with a small attic space -- framed out with 2x4s 24 inches on center. Currently, there is just 2 inches of XPS foam attached under the 2x4 rafters, sealed with spray foam at all seams (thermal camera looks like it is sealed pretty well). I believe there is a 3"+ air space behind the foam to a ridge vent.

What would be the best was to add R-value to these areas?


In General questions | Asked By John Carr | Feb 19 16
4 Answers

Batt insulation performance studies?

I've read a ton of material about improper batt installation, but I've yet to find a study that compared the actual measured results from a grade 1 vs grade 2 and so on. Can someone please point me to a one? Thanks.

In Energy efficiency and durability | Asked By Coop Mag | Mar 2 16
8 Answers

Reusing XPS Insulation - it stinks!

In an attempt to be more green as well as save some money we purchased a good amount of used Agtek Foamular XPS 1.5" insulation from a farmer who pulled it from a series of barns he was tearing down. This came in 4' x 21' sheets and was about 15 years old. It is in good physical shape and the plan was to use it under the slab as well as anywhere else we can. Here is the problem: it smells terrible. It was used to line the roof of chicken barns - no ground contact or anything else but it still smells like the inside of a huge chicken coop after several months on the lot.

In General questions | Asked By Michael Grundvig | Mar 1 16
4 Answers

I'm in the research stage of building a large 32' x 72' greenhouse - Any insight would be wonderful

So I am thinking about building a very large greenhouse. I need some insight as to where I might run into issues as I am by no means a master carpenter.

I guess I should start with my credentials here so you guys have a general idea of my abilities. i have worked in a large variety of industries, including flooring, log cabin restoration, framing, painting, electrical and plumbing, fine woodworking. the only places i lack experience is with HVAC.

In Green building techniques | Asked By George James | Mar 2 16
10 Answers

Supporting brick veneer over a roof and thermal bridging

Hi all,

I'll try my best to describe the situation I'm in as clearly as possible. If I fail, don't hesitate to ask for more info.

I am building a 2-story brick home with a single story wing on the side. In an attempt to make things economically efficient, I designed the back wall of the wing to be flush with back wall of the main house. The drawback to this plan is that the brick veneer on the wall above the roof of the wing will not have a lot of support underneath it to rest on.

In Green building techniques | Asked By Clay Whitenack | Mar 1 16
4 Answers

Attic insulation: open cell or cut and cobble rigid foam?

Hi, I live in climate zone 4a and have a conditioned attic to insulate between rafters. Reading about moisture condensation issues, I looked into closed cell spray foam. Turns out that no spray foam company wants to install a type of foam that has low global warming potential such Icynene EcoSeal Pro. So that leaves me with open cell or rigid foam. I understand that both may let moisture laden air condense against the underside of the rafters, for slightly different reasons. Which method is less risky in that respect?

In General questions | Asked By matthias paustian | Feb 21 16
3 Answers

Cold house in Southern California

Thanks to a giant ash tree in front (east side) of our Southern California house, we almost never need to run the air conditioning, which is great. Downside is, our house is uncomfortably cold even when it's 75 outside. We're thinking of remodeling. Is there anything we can do to use the natural climate to make the house warmer in the winter without making it warmer in the summer?

In Interior design | Asked By Donna May | Mar 1 16
1 Answer

Insulating and ventilating a 1918 Bungalow


Feeling green in every way here. I'm in Seattle renovating a home I bought last November and seeking a strategy for insulation/ventilation. I will be installing and budget is a concern - but I also want to do it right and am a meticulous worker. There are multiple layers of cedar siding on the house and shiplap sheathing. There is no insulation on the main floor and shiplap on the inside of the studs covered with wallboard.

In General questions | Asked By Ian Funk | Mar 2 16
4 Answers

EPS under footing

Am looking to use EPS under both footings and slab in a new construction

Does EPS type 2 meet Ontario building code for Footings ?
Does EPS type 1 or type 2 meet Ontario building code for basement slab ?


In Building Code Questions | Asked By Steve Babcock | Feb 29 16
2 Answers

To vent or not to vent a crawl space in the Pacific NW?

I bought a house in the city of Goldbar half way between Seattle and Steven's Pass.
The roof is metal and has gutters on one side only; so I have rain falling to the ground near the foundation.

There is a crawl space: about 40" tall. There is no standing water. The ground has a poly vapor barrier that covers entirely and part way up the stem wall. The stem wall is concrete and has not been treated or covered. The 2X12 floor joists are full of bat fiberglass insulation. No visible mold.

In General questions | Asked By Jim Mayer | Feb 29 16
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