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6 Answers

Insulation around basement drain pipe?

We are buying a new house with a basement that we'd like to finish. We are in climate zone 4A, and there are no moisture problems in the basement. The floor cracks in the picture are (reportedly) from 6 years ago when the sump pump failed. We will be installing a backup pump.

In General questions | Asked By Daniel Ems | May 25 16
2 Answers

Cathedral ceiling rafter cavity and insulation

I am trying to figure out how best to use Rock Wool in my cathedral ceiling with the space that I have. I am using 2 x 12 rafters. I am not using spray foam. I was going to build my vent baffle from xps sheets for a 1" air space sub roof sheathing...I was even willing to shrink that space down if needed. I live in zone 3 and would like at least R-35. So with my rafter space I start out with 11 1/2" inches. No matter how I figure it with rock wool batting, I either end up with 2" of dead air space that should be filled with something or 1/4" too much for the space.

In Green building techniques | Asked By Scott Smith | May 26 16
17 Answers

Direct vent vs power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

In Mechanicals | Asked By Erik Addy | Mar 8 16
6 Answers

Slab insulation

I need to insulate a slab and usually use rigid foam. However this project is a woody area and there are lots of termites nearby and I know they love foam. Is Roxul drainboard or rock wool a good option in this case?

In Energy efficiency and durability | Asked By James Haug | May 25 16
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
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