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6 Answers

Log home DER Ideas?

I am a long time reader of GBA and, as a result, would not generally even go near a log house if I was interested in energy efficiency. That said, I find myself considering one due to its location, location, location. Given that, I would like to get some opinions about the best ways to go about retrofitting the house so it is at least reasonably energy efficient. Cost counts, so 'tear it down' options aren't all that helpful to me.

In Energy efficiency and durability | Asked By Rob Shuman | May 31 16
4 Answers

Is R-1 fan-fold insulation cost-effective as vinyl siding underlayment?

I am installing vinyl siding on a home in Pittsburgh PA as part of a HUD financed project. As such, HUD has supplied the specs. The requirement is for R1 fanfold followed by Tyvec. I think that the principal function of fan fold has traditionally, pre-house wrap, been to limit air infiltration (not provide R value), a function that is in this case served, redundantly, by the by the Tyvec.
There is almost no wall insulation and no plans to install any soon but there is adequate attic floor insulation.

In Energy efficiency and durability | Asked By Thomas Rydle | May 29 16
2 Answers

Retrofitting insulation: heat loss/gain where ceiling meets the wall

Hello all,

As part of my efforts to air seal and insulate my home, I just purchased a new FLIR infrared camera. First, what a cool tool for an energy nerd! It has instantly identified areas of the home on which to focus.

In Green building techniques | Asked By Brian Gray | May 31 16
31 Answers

Exterior rigid foam and re-siding project

I'm seeking input and opinion. I'm looking to re-side with the dread vinyl (need the low maintenance for my two story house). My 40 year old post and bean house has interior sheetrock, 3.5" of fiberglass batt insulation with kraft paper, rough cut full 2x4 studs on 24" centers, plywood sheathing (I think 5/8"), paper (a mix of Tyvek and felt), and cedar shingles. Shingles and paper will of course be removed, sheathing inspected in the process. I'm in zone 6.

In Energy efficiency and durability | Asked By Howard Gentler | May 2 16
5 Answers

Instananeous hot water with a tank

I'm looking for the manufacturer of an instantaneous hot water heater with a thirty gallon tank mounted above it. The manufacturer advertises it as a complete unit. Any info will be appreciated.

In Mechanicals | Asked By Scott Goodman | May 29 16
3 Answers

Metal roof and wall assembly in Los Angeles

Could you advise on my roof and wall assembly? I want to do better than code and local building conventions (leaky stucco houses) , but don't want to: (1) waste money since the climate is mild; (2) make inadvertent mistakes by diverting from what's tried and true here, and by indiscriminately applying lessons that are meant for more severe climate.

What's your opinion of the most cost effective spec for this climate?

In Green building techniques | Asked By Claire L. | May 23 16
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
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
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
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