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1 Answer

Can wired floor heating cause EMF issues?

I am considering floor heating for my bathroom remodel even for my first floor kitchen and family room. I now have gas forced hot air heating.

For electrical wires under the floor, I have concerns on EMF. But for hot water pipes under the floor, then leaking is my concern.

Please advise.

In General questions | Asked By meitien hsing | Jul 10 14
21 Answers

Post your cut-and-cobble stories

I have decided to write an article on the topic of Cut-and-Cobble Insulation. Even though I sometimes scoff at the technique, calling it an unprofessional method beloved by homeowners, I must admit that I have used cut-and-cobble myself. Sometimes, the method makes sense.

For those who don't know, the term refers to the insertion of strips of rigid foam between studs or rafters. Each rectangle of rigid foam is sealed at its perimeter with caulk or canned spray foam.

So I'm asking for help.

In Energy efficiency and durability | Asked By Martin Holladay | Nov 13 13
2 Answers

Foil-faced polyiso left exposed longterm - impact to R-Value?

A client's deep energy retrofit got started but stopped about 16 months ago, right after the foil-faced polyiso was installed but before the siding was installed. All polyiso joints and almost all edges were taped and sealed. The tape looks great (pretty amazing after two very hard zone 5 winters).

In Energy efficiency and durability | Asked By Kristen Simmons | Jun 25 14
4 Answers

Why spend so much (any) effort insulating the building slab?

I have just enjoyed reading 2-3 years’ worth of blog posts on the site and (Living in Australia) I am intrigued by how much effort and resources (foam) is used to insulate a home’s slab/basement from the ground in some of the high performance builds.

Surely doing this just introduces complexity and opportunity for movement of the slab? Should houses even have basements anymore? They seem like they make it much harder to insulate your building envelope. The only advantage would seem to be if you wanted to utilise the thermal mass of the slab.

In Green building techniques | Asked By David Hall | Jul 2 14
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
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