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1 Answer

Placement of radiant heat tubing in concrete floor assembly

I am building a home in zone 5, Northern NJ. I am exploring the option of a creating a steel/concrete slab to encompass the entire first floor. 9' sub-grade foundation walls (likely ICF) would support steel floor joists/beams, upon which Q-deck followed by rebar and poured concrete would complete the main floor slab. (structural engineer is looking at it, I priced the Hambro D-500 system, more than I liked, will compare to Q-deck/rebar/concrete) I am thinking of embedding radiant heat tubing in the structure, that would allow me to create a thermal slab of considerable mass.

In Energy efficiency and durability | Asked By Sal Lombardo | Mar 28 13
19 Answers

Efficient low-cost thermal water/space heating

I am working on a project with an engineer friend,
we are trying to develop an efficient low cost solution to thermal solar energy for northern climates.

I believe that what deters most owners from using the possible free/green solar heating
for their residences is the payback and up front cost of thermal systems and PV systems
( at least here in canada )

I've seen quotes in the 5000$/kw installed PV which just doesn't make any sense
( when we can all purchase 25 years mitsubishi panels for ~ 1$/w )

In Green products and materials | Asked By Jin Kazama | Mar 22 13
4 Answers

What US jurisdiction first published insulation value tables - for new homes - in a building code?

I am researching energy efficiency objectives in codes and regulations, in Canada and the US. The first Canadian residential insulation value tables appeared in the (provincial) 1975 Ontario Building Code. I know that California's 1978 "Title 24" introduced even broader energy conservation measures. However, I do not know what US jurisdiction (state or city) was the first to publish insulation value tables for new homes, in a building code. I would appreciate your suggestions ...

In Building Code Questions | Asked By Marshall Leslie | Mar 27 13
1 Answer


Assume the following wall:

- 2x framing
- 1/2" sheathing
- 2 layers rigid insulation (staggered seams)
- WRB (assume separate from rigid insulation)
- rainscreen strapping
- lap siding

If the air barrier is at the sheathing layer, and the water barrier is the WRB, should (need) both or either layer of rigid insulation be taped? and if so why? If experience is a guide, I'm all for over-doing-thinking everything, but alas money is finite, and fancy tapes ain't cheap. To tape all seems like wearing a couple belts and suspenders.

Thanks in advance.

In Green building techniques | Asked By Andrew Thompson Zone 3a | Mar 27 13
3 Answers

Metal warehouse/shed retrofit

We're converting an old Butler metal clad warehouse (or storage shed) into a house. Due to local zoning codes, we cannot tear down the existing envelope. This is an urban location and the adjacent building walls are a mere 3" away.

The idea is to keep the existing corrugated steel panels (which are not leaking) and spray closed cell foam as both air & water barrier; to a thickness of 2" clear of the corrugation. Then we would tilt up sections of wall between the horizontal purlins that are @ 7ft vertical spacing (~ 20ft clear height).

In Energy efficiency and durability | Asked By Terl Banks | Mar 25 13
3 Answers

What could cause condensation inside my exterior walls?

I just started a bathroom remodeling project. When my contractor removed the tile off the walls in the shower and around the windows, the insulation was wet. Condensation seems to be the cause. The question is, how do I eliminate the condensation problem before re-tiling my bathroom? I got new siding three years ago and Tyvek was installed under my new vinyl siding. The Tyvek appears to be installed on top of the plywood without any additional insulation.

In General questions | Asked By kim tomczyk | Mar 27 13
5 Answers

Critters and waterproofing

I have an older garage with walls build with 2x4x8 that are spaces 24" apart. The siding is just overlapped wood.

I am planning to reinsulate this space and I have already removed the old insulation (fiberglass and foam combo).

I now see the wood, it's in fairly good shape with noticeable small gaps in the overlaps. I want to close up these gaps somehow, what is the recommended best solution for this.

My primary concern is critters as I am using the garage for food storage and want to make sure everything is sealed up good.

In Green building techniques | Asked By James Cann | Mar 22 13
1 Answer

Chemical sensitivity - tobacco smoke from neighbors

I live in an attached row house (2-family) that is over 100 years old. Recently,, the neighbors on either side of me have rented apartments to smokers. Previously, there was one smoker but, now there are four. It has made our lives unbearable. There is cigarette smoke everywhere. It's on our linen, on our walls, even on my hands. Having stated that, I figure our only two options are to move from a home we have lived in for thirty years or to try and resolve the issue some other way and stay at home.

In General questions | Asked By Ana Echevarria | Mar 27 13
0 Answers

HVAC contractor

Looking for a residential HVAC contractor in Boston that knows high-performance systems. Ideally it would be a company that has an in-house mechanical engineer.


In Mechanicals | Asked By Aaron Yankauskas | Mar 26 13
2 Answers

Insulating attic trusses for storage only

I just read your blog on roofing rules. I need the storage space so I am going with room in attic trusses. I am just going to use the space for storage.

In General questions | Asked By Tim Dunham | Mar 25 13
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