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9 Answers

Seeking insulation recommendations

I work with Habitat for Humanity in upstate SC (zone 3 - warm-humid), and we are researching practices to improve the energy efficiency of the houses we build.

We have been insulating the attic ceiling with blown-in fiberglass but are leaning towards insulating the whole building envelope now (cathedral ceilings and sealed crawlspaces).

First, is it cost-effective to put the HVAC unit and ductwork in the conditioned attic rather than the crawlspace?

Second, what type of insulation should we use in the roof?

In Green building techniques | Asked By Dylan Hillman | Jun 23 16
15 Answers

Eastern Canada 'pretty good house' Insulation strategies

I've read so many articles my head is spinning. I'm building in New Brunswick Canada which appears to be equivalent to your climate zone 7. I'm endeavouring to build a pretty good house meaning efficiency to the point of diminishing returns aka maximum value. One of the major challenges I have here is reconciling good building practices I'm reading about here with the capabilities of local contractors. With that said, I have a few questions.

In Energy efficiency and durability | Asked By Barry Reicker | Jun 14 16
3 Answers

5-inch EPS foam

Hello, I am looking to build a 24x30x10 pole barn to use as a shop/ extra garage. I am not planning to use concrete on the flooring just yet because of the cost. Eventually I would like to pour a slab though. I am researching insulation and think I will use a radiant barrier for the roof to under the metal sheets to reflect the roof heat. Actually the siding is metal as well. I was also given (84) used but in great condition 4x8 sheets of 5" eps foam. I am trying to figure the best way to go about it all. Any would be grateful for any suggestions.

Jeramia

In Green building techniques | Asked By Jeramia Johnson | Jun 29 16
6 Answers

Insulating the underside of a concrete deck

I have a 2-story garage project where the lower level is built with ICF walls...R-25....and PEX radiant heated floors with an R-10 underslab insulation but the ceiling consists of the metal concrete pans and +/- 8" of concrete and rebar. Assume that space above is unheated.....it might also get insulated and heated from time to time when the homeowner needs to do automotive work.....but in general it will be unheated.

In Energy efficiency and durability | Asked By Jonathan Scholl | Jun 27 16
6 Answers

Insulation opportunity: re-roofing a 1922 house

Hello,
I've scoured the archives as best I can and despite lots of great information I've had trouble applying what I've learned to my specific project. Our house is a 1922 craftsman style home with a finished attic. There is currently no access to the unfinished edges or peak of the attic so we're hoping to upgrade our insulation situation while the roof is off.

The house has gable vents that access the unfinished corner edges and peak (4 per side of house).

In Energy efficiency and durability | Asked By Jeremy Cram | Jun 28 16
11 Answers

Anyone have experience with Chilltrix equipment?

A client has asked me to evaluation Chilltrix HVAC systems:http://www.chiltrix.com/small-chiller-home.html.

It appears to be an inverter driven mini split style system that uses a chiller rather than a condenser. I am assuming that it uses and expels significant amounts of water as it does not use a refrigerant, but their documentation is not very specific.

Any feedback would be appreciated.

In Green products and materials | Asked By Carl | Oct 4 15
41 Answers

Best exterior wall design within standard 2x8 dimensions

I have been reading several of the GBA posts and articles and I don’t seem to locate the answer to my question so I wanted to drop you a line by email.

I am located in Saskatchewan, Canada and currently have a house under construction that is well under way. That being said I won’t over complicate it with detail but the house is not a high efficiency design and I am not and don't pretend to be knowledgeable on a lot of points that are covered on GBA.

Hhowever, this is what i have

Construction detail:

Southeast corner of Saskatchewan, Canada 15 miles north of North Dakota

In Energy efficiency and durability | Asked By chad online:) | Feb 21 16
3 Answers

Closed-cell foam versus thermal bridging

I have read several of Martin's articles and reader responses regarding the benefits of using closed cell spray foam on the underside of unvented roof decks. Because it is vapor impermeable, you can spray the underside of the roof without fear of vapor migration to the cold sheathing...so long as it is the proper R-value..... which would then cause rot over time. That's all good. In a cathedral ceiling or gable end wall, what happens to the rafters or studs which cannot be encased in the foam due to the need for drywall?

In Energy efficiency and durability | Asked By Jonathan Scholl | Jun 27 16
5 Answers

Two layers of insulation or one?

We are installing 2" of Hi-load XPS rigid foam insulation under a heated slab in zone 4a and we have the option of doing 1 layer of 2" insulation or 2 layers of 1" insulation. I'm wondering if there is an advantage to overlapping the seams or if it's inconsequential at the end of the day. We will be taping the seams.

thanks,

bigern

In Energy efficiency and durability | Asked By Big Ern | Jun 27 16
15 Answers

Geothermal vs. air-source heat pump

I have researching and getting quotes on hvac for a while now.. It is getting to crunch time.
Well insulated, tight house.

All three quotes include:
3 units, 3 air handlers, each zoned 3 times. Rigid Trunks and short flex runs.

option A. Carrier 18seer 25vna08... 5 stage. ( I don't like the potential harmonics problems of their greenspeed)

option B. Lennox x25 top of their line variable.

option c. Waterfurnace 7 series geothermal units. horizontally drilled ground loop.

In General questions | Asked By Dean Sandbo | Jun 22 16
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