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3 Answers

How did you connect the heat pump to the ventilation system?

I am building my own home in central Maine using a double studded wall with 8" of Thermax between the studs. My heating contractor says I can't connect the heat pump to the ventilation system.

- art

In PassivHaus | Asked By Arthur Taylor | Nov 24 13
3 Answers

HRV help!

We are building a 2600-2700 sq ft home in VT.
Using spray foam insulation.
Told we need HRV ...
We do not know much about the various systems but with our open floor plan are having
a difficult time with duct work/vents - not many walls to put them in.
1. Are there any systems that hands down work better
2. Aret there any systems that use smaller or minimal duct work?
3. Any particular HRV systems to avoid? Think FanTech is what is spec'd.

In General questions | Asked By Elizabeth Croes | Oct 19 13
5 Answers

Our water heater needs to be replaced and we are considering getting a heat-pump water heater

Our water heater needs to be replaced and we are considering getting a heat-pump water heater. We could really use some advice as to whether or not this makes sense for us.

Our current water heater is still under warranty, allowing us to replace it with a 5 year unit (current unit is a GE 40 gallon natural gas-powered tank). We are a family of two adults and one 3 year old. We could get $1,050 rebate if we bought one before the end of the year.

Other details:

Therm cost: current month 88.1¢, last month $1.36

Klw cost: current month 10.3¢, last month 10.5¢

In Mechanicals | Asked By Leah Marshquist | Nov 25 13
4 Answers

One more cold sheathing question

I see that cold sheathing issue has been thoroughly discussed, including an excellent Martin's article. The takeaway I got (right or wrong) is "eliminate air infiltration, allow wall to dry at least in one direction and don't worry". This is happening in Northern Virginia, ASHRAE Zone 4, 111 days with freezing temperature a year on average. House was built in 1986.

In General questions | Asked By Vladyslav Ovchynnikov | Nov 25 13
5 Answers

I need some help (advice on windows)

I'm in the process of building a new house. I am zone 6, I have the house orientated with lots of glazing on the south side.Trying to gain as much heat from the sun as possible. But i don't want to get cooked in the summer. I have external shading designed on that side. I have a R-20 under my slab, R-30 on my foundation walls, R-40 walls, and a R-60 cap. I am shooting for a .6 ACH at 50 pascals or less.

In PassivHaus | Asked By Kirk Nygren | Nov 21 13
3 Answers

Is it necessary to use a rainscreen when installing fiber cement siding over Zip wall sheathing?

I am trying to keep the budget down on the siding install on my own home

In General questions | Asked By Richard Shea | Nov 24 13
7 Answers

Why don't we use plastic as a barrier between the ceiling and a vented attic?

I have been thinking about this. Why couldn't a builder staple a 2' x the length of the top plate piece of plastic to the top plates of the walls before the rafters are set? This piece could then hang down a foot on either side of the wall and still leave the ceiling open for electrical. Then, once its time to close up the ceiling, you could poly the whole ceiling and have an ample piece next to every wall to tie into and gett a good tape seal on. It seems like this could be much more efficient than using plywood/osb for an air barrier.

In Green building techniques | Asked By ben grzadzielewski | Nov 24 13
3 Answers

Notable quote on building cost

In the current issue of FHB (Jan 2014, No.240), there is an article by Steve Baczek on page 50 called "Designed for Success," part one of "The Passive House Build." At the end of the article the author makes a very nicely worded statement about the cost issue associated with Passive Houses, which can be applied also to the PGH level of house. I thought it worthwhile to draw attention to the statement as a "notable quote of the week."

In Energy efficiency and durability | Asked By Dick Russell | Nov 24 13
3 Answers

How long to wait before painting spray foam insulation with fire retardant paint?

We are general contractors and sub out the spray foam insulation jobs. Some contractors paint the fire retardant on right away and others say they have to wait a day and thus come back to the job later to paint. I'm trying to find out which is actually right. Do you have to wait 24 hours to paint the foam or not?


In General questions | Asked By Nancy Tang | Nov 25 13
1 Answer

Blown-in cellulose condensation risk?

So what is the final word on blown-in cellulose insulation in a pre-existing wall? I have plaster walls on 2/4s with wood board sheathing wood siding and shakes on the outside. If I blow in insulation will condensation form on the outer wall causing mold and paint peeling?

In Energy efficiency and durability | Asked By Seth Rutledge | Nov 24 13
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