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23 Answers

Raised Heel / Energy Truss

My builder is about to order trusses. He is not familiar with raised heel / energy trusses. The bottom chords are 12in. How do I have him describe what I'm looking for to the middleman lumber yard guy, placing the order with boise??

I want to make sure they don't mess this up. They are both "old school"! Which is mostly a good thing:)

In General questions | Asked By stephen edge | Jan 7 11
7 Answers

Spray foam insulation post-install chemical smell (not rotten fish)

I've read many articles on this subject, but I wanted to ask a more specific question as my case doesn't seem to match the other's horror stories with poorly-installed Spray Foam Insulation.

In Green products and materials | Asked By Scott Roberson | Sep 10 15
3 Answers

REMOTE wall — single vs. double EPS layer

I am in the planning phase of a REMOTE wall house with construction beginning in June 2016. I have been talking with a foam supplier who is pushing me toward a single ~5" layer of foam instead of the two layers of 2 inch I had been planning. There are a number of advantages to the single thick layer approach - reduced labor and a significant financial savings are two of the most appealing benefits. However, I am concerned that having seams in the foam that run straight through to the housewrap will cost me efficiency vs having a double layer of thinner foam with staggered seams.

In Energy efficiency and durability | Asked By Jim Tyler | Sep 24 15
8 Answers

How safe is a polystyrene Styrofoam board for me to use practically?

I bought an insulation board from a local hardware department superstore, and I have concerns of it blocking my vent. I do have a couple of magnetic vent covers over my vent. However I'm concerned about a few factors. My room get's very HOT easily. I especially learned this when the sun rises every morning it shines against my room and burns it up into an abysmal inferno. It's the middle of the dead winter and I'm waking up finding myself soaked in my own sweat. (Gross!) The board has a R of 75 Degrees (F), and like any other Polystyrene material it is combustible and very easily ignitable.

In General questions | Asked By Mark Granberry II | Mar 28 15
5 Answers

Monitoring energy use of a mini-split unit?

Can I install a kwh meter like this $14 one from China on ebay to measure how much power my new mini-split unit uses? The description says that it works up to 260VAC, up to 100 amps and measures both instantaneous usage (volts, amps, watts) and kw-hours. If it is this simple why doesn't everyone do it?




In Energy efficiency and durability | Asked By David Martin | Sep 21 15
5 Answers

More questions about insulating a flat roof in Chicago

[Editor's note: This question appears to be a continuation of an earlier thread. Here is a link to that thread: Insulating a flat roof in Chicago.]

In Green building techniques | Asked By Andrew Rothstein | Sep 18 15
26 Answers

Has anyone had experience with the Unico small duct system?

I was looking at the top finishers for the department of energy's "Race to Zero Student Design Competition" ( http://energy.gov/eere/buildings/2015-results ) and found the winner used the Unico system. http://www.unicosystem.com/the-system/how-it-works/air-handlers/. I recall actually being in a home in Chattanooga once 15+ yrs ago that I believe had one of these systems, but I really know nothing about them. With the problems associated with finding small enough systems for well insulated homes and cost effective systems...does anyone know if I should be looking at this as an alternative?

In Mechanicals | Asked By Andrew Bennett | Apr 29 15
5 Answers

What is the best way to add wool or rigid fiberglass over exterior walls and under new vinyl siding?

We live in a floating home. It is 2x3 construction, one level. Currently there is aluminum siding over very little fiberglass insulation. What is the best way to add insulation, vapor barrier and vinyl siding over the 2x3 framing? We need to keep weight down so we prefer not to build out to 2x6 wall. From what reading I have done it is all across the board as to what to add and how to avoid condensation and improve insulation and some sound barrier. Thanks!

In Energy efficiency and durability | Asked By Pam Corey | Sep 19 15
6 Answers

Nail fin windows and 4" of foam

I installed the first of my new windows today in the wall with 4" of foam. I set it up as an outie with a 3/4" plywood buck/box to hold the window. I have 3/4" furring around the window. The buck/box is securely fastened to the rough out.

I used 6" screws with plastic washers in the nail fins to studs (mostly) at the corners and midpoints. I used ring shanked nails in the rest of the holes into the furring.

In Energy efficiency and durability | Asked By Mike M | Sep 21 15
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