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28 Answers

How would you spend $40,000?

Hi GreenBuildingAdvisor community - I've been reading off and on for the past 12 months as we gear up to build our home. It's simulatneously depressing and empowering to read through how much is required to properly build a home.

We're pretty happy with the plans (the ones I'm including are not quite the latest - we'll be adding a few windows and moving some interior walls around) but before we do the next round of changes - we need to make a decision about ICF or no ICF. It's a $40,000 question for us.

In Plans Review | Asked By Adam W | Apr 27 16
4 Answers

Connection between GSHP and Zehnder's ComfoFond-L

I wish to make a connection between the ground loop of a Ground Source Heat Pump and the air tempering unit of a Zehnder ERV ventilation system, the ComfoFond-L (which usually utilizes it's own independent ground loop).

I believe that I remember reading about a project in Vermont, perhaps with a government associated housing project, that used ClimateMaster GSHPs and Zehnder ERVs in just this way.

In Mechanicals | Asked By Ted Cummings | May 24 16
4 Answers

Which wall system is appropriate: ICF or double-stud 2x10 with full height veneer stone?

I have a client who wants a thick wall construction with full height veneer stone that comes "right out the ground", so there is no typical foundation to siding detail. This is in zone 5 Canada and I am concerned about building a wood framed wall because I can't really seem to come up with a good detail to vent the cavity I think I need to install behind the stone. Any ideas out there? I am thinking icf is the best way to go but I am open to suggestions.

In Energy efficiency and durability | Asked By Marty Munroe | May 21 16
1 Answer

Roofing / snow & ice safety / uninsulated in zone 5-6

I'm working on a house on the edge between Zone 5/6. It is uninsulated and sadly its going to stay that way.

It also needs a new roof, and that's not optional.

Of course it will keep getting ice dams and large icicles (boo hiss).

My question has to do falling snow & ice. The main roof is a hip. So falling snow/ice raises two issues.

1. Front and back porch already take a beating from above. I can see how the shingles fared (maybe halved their lifespan) How does metal hold up in these situations?

In General questions | Asked By Mark Baker | May 24 16
10 Answers

Fan coils and return air from framing voids

Dear Advisor,

In Mechanicals | Asked By Dan Cullen | May 23 16
8 Answers

What would a weighted average R-value be for a Superior Wall Xi?

I am trying to determine what the weighted average R-value of a Superior Wall XI and XI plus wall is. Does anyone know? I can post cross sectional diagrams if someone can tell me how.

In Green products and materials | Asked By Chaz Steffen | May 23 16
12 Answers

Flashing "innie" windows - tape, caulk, anything at all?

Hi everybody! My builder friend and I are uncertain whether or not we are making mountains out of molehills here, and were hoping to get some feedback on a flashing detail.

This project has a thick wall buildout and "innie" windows: the nailing flange of each window is on the same plane as the house wrap, with exterior insulation and strapping/siding on top of that.

In General questions | Asked By Benjamin Wooten | May 9 16
1 Answer

Floating slab with frost walls — Plumbing and floor framing

We are doing a relatively large expansion. of a small studio space. A much earlier constructed garage/shed to which the studio space was added on to has been removed. We are using an insulated pad with frostwalls. The expansion will include all plumbing. Due to unavailability of a plumber and concerns over the lack of flexibility of cast in place plumbing, we have decided to frame the 4 x 12 foot portion of the pad.

In Green building techniques | Asked By Potter Shaw | May 23 16
11 Answers

Paint choices


In General questions | Asked By Lucyna de Barbaro | Mar 5 16
7 Answers

What is the best airtight LED retrofit for can lights?

I couldn't talk the builder out of can lights on the top floor, so I thought I could fix the problem once he's all done.

In Green products and materials | Asked By Kevin Dickson | May 20 16
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