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2 Answers

Condensation in roof rafters in a metal framed house?

Hi, I am trying to build a metal framed house in Bonsall CA, climate zone 10 in California, climate zone 3 nationally. 13 miles inland from the Ocean about 40 miles north of San Diego. One half the roof will be metal trusses, the other half will be conventionally stacked using 2" x 10" metal rafters. On top of rafters is radiant barrier plywood, 40# felt, followed by Spanish Clay Tiles with O'Hagin vents.

In Energy efficiency and durability | Asked By Peter Coz | May 25 16
2 Answers

No minisplit contractors close by

Would it be stupid to install a Fujitsu or Mitsub minisplit with the nearest Fujitsu or Mitsub contractor 60-75 miles away? Can other contractors work on these?

In Mechanicals | Asked By brad haack | May 25 16
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
14 Answers

Mitsubishi minisplits — horizontally ducted

Sorry - I blv I posted the same in another section. Please ignore this question if it's a duplicate.

We are not fans of ductless units. Therefore, we opted for the hidden horizontally ducted units that Mitsubishi provides. Unfortunately, all the Mitsubishi contractors we talked to have never designed a home with these type of units. Plenty of ductless experience.

In Mechanicals | Asked By Ismail Mohammed | May 21 16
10 Answers

Fan coils and return air from framing voids

Dear Advisor,

In Mechanicals | Asked By Dan Cullen | May 23 16
1 Answer

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
15 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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