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3 Answers

Raft slab edge insulation detail

Hi - I'm building a home in Central Vermont (Zone 6) this summer and had a question regarding slab edge detailing.

In Energy efficiency and durability | Asked By Craig Bunten | May 29 16
36 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
2 Answers

Insulating walk-out basement

I'm insulating a walk-out basement in a new construction. The house is of a double wall design, and will be filled with dense pack cellulose. I understand that for the foundation walls that I can not apply cellulose directly, however I had thought that if I apply a layer of closed-cell either sprayed or laid in in sheets then I should be able to fill the rest of the cavity with cellulose, assuming that there is no concrete exposed. My question is how many inches do I need to use to assure I have no problems with the cellulose?

In Green building techniques | Asked By Geoff Frood | May 29 16
3 Answers

Conditioned crawlspace, floor insulation

I think every drawing & article I've read showed no insulation on the floor of a conditioned crawlspace. So far, I haven't found any recent info on the heatloss into the ground or temperature of the ground below a conditioned crawlspace. There's something in my old ASHRAE fundamentals for a basement floor, but it seems too high. It would seem that if there more than a little heat loss it should be insulated?

In Green building techniques | Asked By brad h | May 29 16
34 Answers

Improvement on the Lstiburek Ideal Double Stud?

Hi all. Please see the attached PDF of a variation on Joe Lstiburek's Ideal Double Stud Wall design (http://www.greenbuildingadvisor.com/articles/dept/building-science/lstib...).

I am trying to go for something a bit quicker and less labour intensive to build, but that is still very vapour open to the exterior (and occasionally interior) to overcome the usual double stud wall shortcomings.

Please fire away with critiques. The main problems I see are:

In Green building techniques | Asked By Burke Stoller | May 6 16
19 Answers


I am obsessing over which pex to use for a whole house manifold installation. The choices are pex-a (uponor) vs pex b (viega).

Uponor seems easier to work with, less kinking, better flow etc.

What I am most concerned with is:

1.longevity (this is my forever house)
2. safety (leaching of chemicals into drinking water)

I am on a well.

Any input as to the longevity and safety of these two different types of pipes?


In General questions | Asked By Dean Sandbo | May 26 16
18 Answers

Has anyone ever kept sheathing warm and saved labor costs this way?

There are a handful of manufactures who make rigid insulation with OSB bonded to the surface (like a SIP with OSB on one face only. But SIPs are not the topic in this post). This assembly is commonly used for roofing but I was contemplating using it backwards as exterior wall sheathing. By backwards I mean fastening it onto the studs so the OSB is touching the studs and the foam is on the outside. By doing this, the osb is kept warm and that desirable thermal break is incorporated as well (after all thats generally the reason to put rigid on the outer face).

In Green building techniques | Asked By sean stewart | May 22 16
1 Answer

Northern bias

I grew up in Iowa, lived most of my life in New England, but now live in the hot humid south. I think you need to focus more on climates other than the cold north. Contributors like Curt Kinder were very useful to me a couple of years ago -- a person who had migrated similarly, but unlike me ( an amateur ) was a pro in his business -- HVAC. Suggest you do what you can to get hot and humid more often, and more important, encourage contributors like Curt Kinder, a person who writes well, and has real-world experience, to re-engage.

In General questions | Asked By Michael M | May 28 16
11 Answers

Windows -- Pretty Good or better in Western Colorado

I am looking for windows for a Pretty Good house I am preparing to build in Carbondale, CO at an elevation of about 6,200 feet. Climate zone is 6B. We get lots of sun here and large diurnal temperature swings, year round. I don't know of any homes in town with air conditioning. I'm looking at Pretty Good insulation levels, R-5-10-20-40-60 and about 6 to 8% south facing glass with fairly low thermal mass -- partial tile floors and 5/8 drywall. Windows on the north and west will be limited. I've heard that 4% overall operable glass is a reasonable target.

In Energy efficiency and durability | Asked By Pat Kiernan | May 27 16
10 Answers

Sun Pump solar heat pump

Does anyone have experience with the Sun Pump solar heat pump, either with the product itself or dealing with the company? It's a relatively new company located in Vancouver BC.

In Mechanicals | Asked By Peter Schonherr | May 19 16
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