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3 Answers

Average cost for air sealing work?

Thank you for your response. I want to be prepared when I call a home improvement contractor. So, I want to ask a couple of questions.
I would like to know what the average cost to this work could possibly be. Also, previously, I had the idea of using foam and then the fiber glass insulation. Is that similar to what you stated? In addition, would cellulose be a better insulator than fiber glass? Lastly, could I have the sealer put in without tearing down walls and forego the insulation, right away?
Thanks in advance for your response.

In General questions | Asked By Ana Echevarria | Mar 27 13
1 Answer

(Composting) Toilet in Floodplain?

Does anyone know if a toilet can be installed in New York City on land located in a floodplain (designated Zone A by FEMA)? What about a composting toilet? Please cite codes and/or case studies. Thanks.

In Building Code Questions | Asked By C. Leigh | Mar 28 13
1 Answer

Radiant heat wall panels?

I am still looking for a heat delivery system for an old house retrofit. I have a new condensing boiler, and love the idea of radiant floors but don't want to rip up the old floor. Staple up under 1 3/4" of old wood doesn't seem like a great idea. Most of the plaster walls have to come down anyway (water damage) and I am wondering why not use radiant in the lower portion of the walls. Exterior walls are 4" (true) and will be cellulose insulated. I feel like there would be less heat loss if I use interior walls but would that be uncomfortable feeling?

In Mechanicals | Asked By Nyle Phillips | Mar 28 13
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
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