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14 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.

Asked By Erik Addy | Mar 8 16
0 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.

Asked By Peter Coz | May 25 16
12 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.

Asked By Ismail Mohammed | May 21 16
16 Answers

HVAC - Gas vs heat pump vs ducted mini split

It seems the general consensus here, on a very tight or "pretty good" house, is for ductless minisplit. I'm trying to understand the economics.

The following parameters are non-negotiable:
1. Climate zone 3A
2. The house will be piped for natural gas for, at a minimum, cooking and outside grill

Asked By c l | May 22 16
1 Answer

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.

Asked By Ted Cummings | May 24 16
8 Answers

Stamped concrete patio near foundation

Hi all,

I have a couple of questions regarding a patio near the foundation of our house. My wife and I have been dealing with water issues in our basement/crawl space for a while now, and we just recently had a contractor in to seal the vent properly, install a membrane along the foundation wall, and add French drains tied into the downspout.

As the last part of this work, we have removed a surface deck that the old owners installed and are looking to install a stamped concrete patio with the same dimensions (14x30) pitched away from the home. Specifically my questions are:

Asked By Ryan Lambert | Mar 19 16
21 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.

Asked By Adam W | Apr 27 16
7 Answers

Sun Pump solar heat pump

Does anyone have experience with the Sun Pump solar heat pump, either with the product itself or dealing with the company? It's a relatively new company located in Vancouver BC.

Asked By Peter Schonherr | May 19 16
0 Answers

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?

Asked By Mark Baker | May 24 16
10 Answers

Fan coils and return air from framing voids

Dear Advisor,

Asked By Dan Cullen | May 23 16
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