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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
19 Answers

Why is our home so inefficient?

We bought an 1,800 sq. foot house in the north Berkeley hills in November of last year. There was a small mold issue which we remediated in December and January. During that time we also did an extensive HVAC upgrade, with a 3-zone heating/cooling system, smaller/more efficient duct work, an in-line dehumidifier, and in-line air filter. (Our daughter is sensitive to mold and other airborne allergens, which is why we installed the dehumidifier and air filter.)

In Energy efficiency and durability | Asked By Chris Durand | May 22 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
7 Answers

Fastening details - deck ledger to insulated slab

I am designing an insulated Monolithic Slab. I plan to install 4" of Roxul comfort board beneath and around the perimeter of the slab.

Does anyone have experience attaching a deck ledger to a slab (or stem wall) that is insulated with Roxul? Or is it advisable to place a higher density product beneath the ledger to avoid compression which may happen with the Roxul Comfortboard?

What type of fasteners are recommended for this application? Would a standard wedge type concrete fastener like a red head work?

Other solutions?

In Green building techniques | Asked By Michael Iacona | May 19 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
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