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10 Answers

Need help with recycled polyiso insulation in attic

I found a great deal on recycled polyiso boards that were once a roof on a commercial building with EPDM rubber over it. Each board is 4 foot by 4 foot and 4 inches thick.

I am going to use them in a 1830 post-and-beam house. The boards are going to be going in the attic. There is currently no insulation or vapor barrier in there. The house is in upstate NY and sees some seriously cold winters (at least in the past).

In Energy efficiency and durability | Asked By Larry Broderick | Feb 7 12
4 Answers

How do you attach a large amount of insulation to a concrete wall?

The house I am building in zone 5a will have concrete walls (2 story) for high thermal mass. I would like the walls insulated to R-30, but am concerned about how to attach so much insulation. Will 5 inches of polystyrene get me to a R-30 and how will it attach to the walls? Is there a better way to insulate concrete?
Deni

In Green building techniques | Asked By Denise Elliott | May 29 12
4 Answers

Worth worrying about heat loss through aluminum door threshold?

I've just replaced a door between the house and unconditioned garage, where the temperature regularly gets up to 110°F in summer (i.e. the garage is basically a greenhouse). I was really focusing on air-sealing so I completely replaced the jambs with exterior door jambs with Q-lon etc.

The bottom of the door I wasn't sure about, and I had an aluminum threshold with a rubber gasket handy so I put that in at the bottom of the door (removing ~3/4 of an inch of door).

In Green building techniques | Asked By James Howison | May 24 12
8 Answers

Heating and cooling a ICF and SIP house

Hello, I am building a ICF foundation and SIP home in VT.
I am looking for suggestions on the best affordable system to Heat / cool and vent this home.
Right now I am leaning towards a HTP Versa Hydro Heating system PHE-130-80S
I was planning on putting radiant in the slab, and have a forced hot air system for the 1st and second floor and prep for future solar hot water and prep for running a condenser to cool in the future.
My foundation is in and getting ready to pour the basement floor.

In Mechanicals | Asked By Andrew Tarantino | May 29 12
1 Answer

What kind of metal roof and radiant barrier would work best in Palau?

My wife and I are building a house in Palau. Hot humid climate. We plan to use a metal roof of some sort and a radiant barrier. We will have several photovoltaic panels on the roof. We would like to do water catchment. We want the roof to stay on during high winds.

Any suggestions as to materials, designs and websites aimed at building in the tropics?

In Green building techniques | Asked By Gerhardt Braeckel | May 29 12
8 Answers

Triple-glazed windows and passive solar: Does it make sense to install triple glazing on south-facing windows?

I live in Southern British Columbia, so we are primarily heating area. No air conditioning required. We have excellent southern exposure, and large overhangs on south side. We plan to install triple-glazed windows on N. E. and W. walls, but not sure if triple glazing makes sense on the South side. Will triple glazing limit winter solar gain?

In Energy efficiency and durability | Asked By David Slade | May 21 12
0 Answers

Results of window buyer satisfaction survey

BuildingGreen has published the results of its survey asking window purchasers to rate their satisfaction with windows from a wide range of manufacturers.

On the top of the heap were Marvin and Optiwin. Bringing up the rear were Owens Corning Innovision Windows, Paramount Windows, Sorpetaler Windows, Stanek Windows, and Willmar Windows.

The results are published here:
Window and Door Manufacturers: Customer Ratings

In Green products and materials | Asked By Martin Holladay | May 29 12
9 Answers

Basement sub-slab insulation

I should know the answer to this already.... I'm in climate zone 6, using the IRC 2009 code. Table N1102.1 requires R-10 insulation below a slab. I've been taking this to mean under the basement floor, but in re-reading it for the 100th time today, I think I've been misunderstanding the requirement. I know it's best practice to insulate under the poured concrete floor in a full basement, but is it required?

In Building Code Questions | Asked By michael maines | May 23 12
4 Answers

Is 1/8" too small a gap for continuous eave ventilation?

Hello-
I'm drawing up a small dwelling, and have calculated that I need 1/8" of continuous soffit ventilation under my eaves.
Will 1/8" suck enough air? It seem awful small considering Lstiburek recommends 2" of ventilation between the underside of the roof sheathing, and the top of the insulation baffles.

I've read that continuous venting is preferred, but maybe it's better to go with (4" round) vents between each rafter tail in this case.

Thanks for your help,
-Richard

In General questions | Asked By Richard Baumgarten | May 28 12
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
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