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2 Answers

Insulation recommendations for a brick & block addition?

Hello GBA,

In Energy efficiency and durability | Asked By Brian Gray | Jul 18 14
8 Answers

Interior air sealing tape

Hello, I'm in the USA and currently constructing a two story addition. I have 14 windows and 2 doors already installed and I'm looking for the best way to air seal them on the interior. What interior air sealing tapes are available that would be used to air seal the rough opening gap on the windows? I've done a lot of searching and can't seem to find many options. Any help would be greatly appreciated. Thanks

In Energy efficiency and durability | Asked By SCOTT KOONS | Jul 16 14
11 Answers

Can a Trombe wall be used in reverse?

New construction, Panama City, Fl, 5,000-square-foot container (18) home facing south on piers. Will have 8' x 40' porch on west and east sides connecting to 8' x 80' porch on south side. Think U shape.

Due to high thermal conductivity of the metal, I was wondering if I could use a Trombe wall in reverse, pulling air from under home and venting it out at top of wall exteriorly. My thought is to remove convected heat transfer between the container walls so less insulation would be needed.

In Energy efficiency and durability | Asked By Les Amoss | Jul 16 14
6 Answers

How to condition an existing crawl space?

Hi. I haven't been here for a while because I thought I had found the solution to my crawlspace problem but alas I haven't. I had been dehumidifying the crawlspace at our beach house with a high capacity Santa Fe dehumidifier which unfortunately got destroyed when the crawlspace was flooded during Superstorm Sandy. Rather that buy a new one, I had a vapor barrier installed, replaced the open vents with insulated smart vents and had the underfloor of the house covered in 2-3" of closed cell spray foam.

In GBA Pro help | Asked By Cherylann Schieber | Jul 17 14
12 Answers

Adding interior insulation on a brick veneer house - Concern about inward solar drive caused moisture issues.

I own a 1929 brick veneer home and have been steadily improving the airtightness and insulation levels. The time has come to consider the exterior walls, which are (from inside to outside) plaster over celotex, 2x4 framing (hybrid balloon framing), ship lap sheathing, tar paper, 3/4" air gap, then brick. The house is 2 stories, and has approximately 2' overhangs.

In Energy efficiency and durability | Asked By Joshua van Tol | May 20 14
3 Answers

Can an HRV be installed in a garage in climate zone 5a?

I just purchased a new spec house and I'm going to install an HRV to improve the indoor air quality. The house is at the very bottom edge of climate zone 5a.

Would be okay to install the HRV in the garage? The AHU and furnace are in the garage along with the water heater, so this would be the easiest place to install the HRV. The installation manual for the Fantech HRV I am considering says it should be installed in a "heated" space but it doesn't specify a temperature.

In General questions | Asked By Patrick Cantwell | Jul 17 14
3 Answers

Gaps in insulation: effect on total R-value?

We recently had blown in insulation installed in the attic of our Cape Cod style house up to an R-49.
But we do have some gaps that couldn't be addressed by the blown-in insulation and those are still to be tackled. The picture below was taken prior to the blown in insulation. June was the first full month with the added insulation but we saw no drop in electrical usage from the June 2013. I know there are a lot of variables, but would the insulation gaps in the stairwell and left side kneewalls (to a lesser extent) negate all the added insulation?

In General questions | Asked By HD S | Jul 14 14
1 Answer

My question is on the suitability and application of foil-faced rigid foam to exterior walls with our climate conditions

I am a homeowner, little sun from Nov to March, average daytime winter temp -8 C, night -15 C, with intermittent -20 C days lasting no more than a week, summer daytime temp, average mid 30 C, night 20 C, with intermittent weeks of high 30 C., average annual rainfall 20 inches, average annual snowfall 60 inches, generally calm, however, can get an occasional rare storm with winds of 20-40 mph and generally low humidity particularly in the winter.

In GBA Pro help | Asked By Marilyn Limbert | Jul 16 14
10 Answers

Rigid foam for hot roof

I am interested in converting our bungalow attic to finished space, and it was not designed for venting. I've heard I can do a hot roof insulation method using spray foam. However, I am a DIY guy by nature, and was interested in methods I've seen using closed-cell polyiso rigid foam and spray foam cans to achieve the same result, at least in walls. I am curious about using this method on a hot roof. Surely it would cause head-scratching with code officers. Would it work, though?

In Energy efficiency and durability | Asked By Asa Bradford | Jul 13 14
3 Answers

Raycore - is it the product for me?

I was pretty much on board with buying Raycore for the 4500 s.f. home I am building in downstate NY, which is steel framed, so I actually don't need any structural value out of the exterior walls other than for supporting the windows and doors (and supporting the walls themselves). I am also going with a wire lathe and stucco on the exterior - Raycore told me I could direct apply the wire lathe and did not have to use any sheathing if I did not need the shear strength, but I am hesitant to do so.

In Green products and materials | Asked By Joe McCarthy | Jul 14 14
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