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3 Answers

What percentage of our total energy is consumed by residential users?

I have heard, seen different estimates on this. Any reliable data anywhere?

In General questions | Asked By David Anderson | Feb 8 11
6 Answers

Will high-density spray foam on the floor of a ventilated attic cause moisture problems in a hot-humid climate?

It's an older home in northwest Florida, the insulation is on the floor of the attic, with a wood tongue and groove ceiling on the living space side underneath. I know that this type of closed cell foam stops moisture, so that could cause the insulation to have condenstation on top and make ceiling joists wet. Does this need to be fixed in some way? Is there a way to cut through areas of the insulation and perhaps replace those areas with open cell foam so that moisture can move through and dry to the inside of the home?

In Energy efficiency and durability | Asked By christian wagley | Feb 4 11
6 Answers

Dense pack cellulose: facts or fictions?

For dense packing cellulose insulation, does it matter if it is blown dry behind netting or done as a damp spray? Any difference between the two techniques in the R-value or convection properties in the resulting wall assembly?

On another aspect of cellulose, is there a limit to how deep a roof assembly can be dense packed? The example I was given is that typical 11 7/8 inch I-joists would pack OK but that 16 inch deep parallel cord trusses are too deep to truly dense pack.

In Energy efficiency and durability | Asked By Donald Lintner | Feb 7 11
3 Answers

Venting a SIP roof

Using metal roofing over SIPs -- cathedral ceiling. Would like to vent roofing. How would this be done?

Thanks--------- Greg

In Energy efficiency and durability | Asked By Greg Gunderson | Feb 7 11
5 Answers

Parking on drain field

Is there a way to use a drain field as a parking space without compacting it?


In Energy efficiency and durability | Asked By Greg Gunderson | Feb 8 11
5 Answers

Conditioning Attic Space when Job is Small

Zone 2A. I've done ventilation baffle/batt insulation of most of the roof decking. What remains is a windowed fascia and associated gable. See attached. The exterior side of the windowed facia is a decorative cedar shingle that I would guess has tar paper beneath. The roof is asphalt shingle. I'm estimating a total of 200-300 sq ft of this remaining area that I'd like to hit with closed cell spray foam. Hard to find a contractor who will do a job that small here in Houston. I could order one of those kits from Tiger Foam and do it myself.

In Energy efficiency and durability | Asked By Mark Inman | Feb 7 11
2 Answers

Inexpensive heat transport?


I'm working for a lab that has a room that gets very hot and very noisy. In the winter we'd like to keep the door open to share the heat from room to the office area, but it's just too loud. Does anyone have a way to transfer the heat from this room to a more quiet office area on the opposite side of the wall?


In Energy efficiency and durability | Asked By Pete Koszulinski | Feb 7 11
2 Answers

A green bathroom floor

When building a bathroom downstairs, is it considered green when you don't tile the floor and leave it concrete?

In Green products and materials | Asked By Carla Giovanoni | Feb 7 11
19 Answers

Blown cellulose in soffits now causing leak

I had blown cellulose installed in my attic last week with sprayfoam sealing of the top plate and Styrofoam baffles placed between each rafter. I also had dense-packed cellulose installed in between each stud in the wall below. We have now had significant snow fall and freezing rain, and today I noticed a leak from the top of a window casing in the wall that was dense-packed. When I went up on a ladder to look at the gutter, I found a significant amount of frozen cellulose protruding from a gap between the slate roof tiles and the sheathing underneath.

In Energy efficiency and durability | Asked By jason shapiro | Feb 2 11
0 Answers

Retrofit spray foam on the bands of a brick house

My wife and I have just bought a vacant 1910 foursquare house in Columbus, Ohio. The exterior walls are structural 2-wythe (c 8" thick) brick walls with a plaster parge, resting on a sandstone foundation. We want to seal the walls with 2 inches of spray polyurethane foam before installing unfaced fiberglass batts in the 2x4 walls that were added by the previous owner on the interior. There is a gap of 2"+ between the masonry wall and the interior framing.

In Energy efficiency and durability | Asked By Mark Waite | Feb 7 11
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