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3 Answers

Would plaster in a vented, unconditioned attic be an issue?

I have a friend who is putting a new roof on an 80-year old house in Pittsburgh. She's experienced problems with ice damming in the past and is considering adding a ridge vent along with the new roof. The attic is finished with a hardwood floor and plaster/lath ceiling. They recently added insulation in the attic floor.

Would the plaster need to be removed if a ridge vent were added?

In Green building techniques | Asked By Stephen Horvath | Aug 1 12
6 Answers

What is the best practice and material to insulate my crawspace ceiling?

I own a 22'X32' ranch home(vacation property) in upstate New York. I had the crawlspace "encapsulated" last year which took care of the bulk of the moisture problems. I'm left with fiberglass batts in the ceiling(floor of the living space) that are starting to fall and make a general mess of the space. Is closed cell spray foam a good option to fix this problem? What other issues might I encounter? What about rodents? They try to move in every fall, but I've been able to keep them at bay with prudent use of traps.

In Energy efficiency and durability | Asked By David Jackson | Aug 1 12
2 Answers

Can the DOW product Perimate be used as an exterior foam insulation and rainscreen in one?

DOW has a Styrofoam product called Perimate, it is a foam sheathing that is typically used in exterior foundation applications in which dovetail grooves allow water to channel out. http://building.dow.com/na/en/products/insulation/perimate.htm. Could this product be used as an exterior sheathing and rain screening in one product? I would apply bug screen at the bottom and use corravent s-400 underneath the freeze board to allow for some air to travel behind the siding.

In GBA Pro help | Asked By Jason Macdonald | Aug 1 12
7 Answers

Air Sealing from the outside

Looking for some input. We are starting a project soon in Cambridge, MA. The house is a large structure built in 1869. Air sealing the envelope is a part of the program. We are stripping the two (2) layers of existing siding to expose the sheathing. We are not removing the existing decorative trim (cornice, large corner boards, window trim, etc) so there is not an opportunity to add much rigid insulation. We are presently discussing the approach to air sealing the sheathing. The architect suggested fanfold insulation with tape.

In Energy efficiency and durability | Asked By Bruce Friedman | Jun 1 12
20 Answers

Do I need another air barrier?

I've extended my rafters with luan gussets and 2x4s behind a future knee wall in my raised heel, attic trussed house. Zone 6. I've also built 1 inch vent chutes out of 1inch tuff r polyiso. Now I can fit two 5.5 inch roxul batts in the rafters, under the poly ISO chutes. Question. Do I need an air barrier under the roxul? If so, does it also have to be a fire rated? If not fire barrier rated, what are my options? I'd like to avoid sheetrock and use wood up in this part of the house. The ceiling below is 1/2 blueboard and plaster.

In General questions | Asked By stephen edge | Jul 30 12
17 Answers

Geothermal vs. air-source heat pump

I am building a tight insulated home in zone 6 and deciding wether to choose between ground water heat pump and air heat pump. After the 30% tax incentive there is not much increse in cost for the geo system. I am being told differnet stories in regard to system performance and longevity of equipment ( depending on what side of the fence your on). I am hoping to be in this house for the duration and willl be the last home I live in until my kids have to make the choice of where to send me. Dana

In Energy efficiency and durability | Asked By Dana St.Ours | Jun 2 12
4 Answers

GSHP Vs whole-home dehumidifier


I am looking at retrofitting my home with a GSHP (please see the below thread for details):


I am also planning to have an HRV and a whole home dehumidifier (Lennox 65-pint) installed as part of the new setup. My question is:

In Energy efficiency and durability | Asked By Venkat Y | Jul 23 12
6 Answers

Insulating recessed lights where there is no attic

I have an interesting problem. We have seventeen, 6" recessed lights in a ceiling that has no attic above it. We conducted an energy audit (we're putting in a 9 kw solar system and a host of other related changes) and found these to be a serious source of energy loss. The area where these are located is a single story, family room that just has the heat sucked out of it in the winter. These recessed lights are like chimneys.
While I am replacing most of our recessed lights with LED's, this one area I haven't touched as I need to insulate first

In Energy efficiency and durability | Asked By Alex HIllman | Jul 29 12
1 Answer

High solar gain windows in NJ?

I'm building a super-insulated house, 12" cellulose filled double-wall in South Jersey, R60 roof. I think the HDD are about 5000 and the CDD are about 1000. Should I be using high solar gain windows? Would they be cost effective?

In Green building techniques | Asked By Michael Arnold | Jul 29 12
4 Answers

Construction-detail Drawing Library

Would love to see drawings pertaining to double-stud walls or links to other resources providing these details. Any plans to create a library section dedicated to this subject?

In Green building techniques | Asked By ken dupuis | Jul 27 12
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