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4 Answers

ERVs and formaldehyde

In the Allison Bailes interview with Dr. Iain Walker http://www.greenbuildingadvisor.com/blogs/dept/building-science/intervie...
the emerging concerns about formaldehyde transfer (or non-transfer) are discussed at the end. As stated in the interview, it's hard for the purchaser to know the exact extent of the issue with particular units, but Dr. Walker does describe the 2 methods of exchanging moisture, wheel and membrane with the latter being preferred.

In Mechanicals | Asked By Greg Wilson | Jul 8 14
4 Answers

Air sealing metal electrical boxes

I'm looking for a good way to air seal metal electrical boxes. Local code requires conduit for all electrical, and no plastic boxes.

All of the solutions I've found are for romex and plastic boxes. I know there must be something for conduit and metal boxes.


In Green products and materials | Asked By James Lenihan | Jul 7 14
2 Answers

Minisplit efficiency - multiple single zone vs single multi-zone

Hello all,

In Mechanicals | Asked By Brian Gray | Jul 2 14
1 Answer

Rim joists - where spray foam interior and rigid board exterior meet.

I'm in a climate zone 5 area and have a 3' crawlspace with close to 6" of closed cell spray on the interior of the rim joists. I'm about to re-side possibly with Hardipanels, and insulate from the outside- planning on 2 layers of 1-1/2" of reclaimed polyso, held on with 3/4" furring strips over Tyvec for a rainscreen, well secured , enough to hold the Hardiboard. My intent is to run the siding roughly 1' below the top of the cement block. My question is- where do I end the polyso?

In Energy efficiency and durability | Asked By stu m | Jul 9 14
6 Answers

Slab on grade thickness

Just a quick question on how thick the slab should be on a slab on grade house?...thanks,Bob

In General questions | Asked By bob holodinsky | Jul 9 14
10 Answers

Does anyone use hydronic underfloor heating systems to move passive solar heat around the mass?

I'm in the early stages of planning a new build. I'm considering a heat pump underfloor heating system in concrete slab. The house will be carefully optimised for passive solar gain as well. Has anyone heard of using the underfloor plumbing to move heat around the slab from areas receiving direct solar illumination to other parts of the slab?

In Energy efficiency and durability | Asked By Felix Collins | Jul 8 14
8 Answers

My rant regarding the energy efficient mobile/modular homes :-)

I do not understand why people are trying to reinvent the wheel regarding the actual construction of mobile/modular homes. They must have money to burn and time on their hands and that makes me mad because they are charging ridiculous prices.

In Energy efficiency and durability | Asked By Anneal G | Jul 1 14
23 Answers

For southern exposure, what do you think is the better glazing option: 1. U=.29, SHG=.49 or 2. U=.19, SHG=.37 ?

Both windows would be installed near Green Bay, WI, climate zone 6. The lower u-value window is vinyl and the other is fiberglass, but aesthetically, both are acceptable and equal for my tastes. The vinyl are manufactured by Wasco Windows (based near Milwaukee, WI) and the fiberglass alternative are Marvin Integritys.

The square footage of glazing along this wall is approximately 5.5% of the floor space. The finish floor will be a 5" concrete slab that will have no additional floor covering.

In Energy efficiency and durability | Asked By Rick Van Handel | Jul 7 14
0 Answers

Where to get Roxul Drainboard in 3.5 inch thickness?

I live near Rochester NY. I am building passive solar home. Does anyone know where I can buy Roxul Drainboard in 3.5 thickness on the east coast ? I have talked to reps from Roxul and can only buy a truck load . Hard for the owner builder to go greener when we cannot get the products. Does anyone know of any cooperative, business or homeowner that has it for sale? Thank you ! Zenith7

In Green products and materials | Asked By michael holler | Jul 9 14
5 Answers

Why hasn't this cathedral ceiling failed?

Climate zone 5, northwest Ohio. Evaluating options for improving a cathedral ceiling in this 1970's house.

In Energy efficiency and durability | Asked By Andy Chappell-Dick | Jul 8 14
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