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2 Answers

Does anyone have experience with the Rheem Prestige Hot Water Heat Pump?

I was excited about using the Sanden CO2 HPWH, but communication with the company was very hit or miss. The local installer they referred me to was very responsive and helpful with technical information. He gave me a quote for $5,900 installed. This was for a 43 gallon tank (the 83 gallon tank, oddly enough, would've been $6,100 installed). Because of the poor communication, and the cost, we had to move on.

Asked By Eric Whetzel | Dec 8 16
4 Answers

Optimum air gap for skylight

Context: a 14x7x6' tinyhouse with 4"-thick polyiso insulation on all surfaces except the windows, which, for reasons that aren't relevant here, must be on the roof.

Several hours of research shows that the optimum air gap for a typical double-glazed window ranges between 13-30mm depending on whom you ask. Charts show that U-value tends to bottom out at around 13mm and slowly climbs up from there. From this research I've gleaned hints that the glazing material and the angle the window is mounted at are factors, but I've been unable to find out how they matter, so I turn to the Community.

Asked By Geva edhrven | Dec 8 16
12 Answers

How important is a thermal break between a house foundation and an attached garage foundation?

Our footings were poured today for a new house and attached garage. The walls of the basement foundation (9') and garage foundation are scheduled to be poured next week.

Looking over the plans, our concrete sub is worried about the 7" thermal break between the basement and garage foundations (no physical connection) as currently drawn on the plans. The separation is there in order to allow us to attach 5" of Roxul Comfortboard 80 to the basement foundation (we'll be doing the same for the whole exterior perimeter of the basement foundation).

Asked By Eric Whetzel | Dec 2 16
3 Answers

How can homeowner find contractor to install rigid foam on top of roof sheathing?

To everyone, but especially anyone in the Chicago area:

Asked By Rebekah Haworth | Dec 8 16
3 Answers

Airflow around mini split compressor

Hi, the installer for my Fujitsu 15RLS3 installed the lineset in such a way that I think it restricts airflow behind the compressor quite a bit. See the attached photo. They wrapped the lines in a circle a bunch of times between the back of the unit and the wall to deal with the fact that the outdoor compressor is less than 15 feet from the indoor unit. In any case, do you think this restricted airflow affects efficiency or longevity of the system and I should ask them to put the lines elsewhere ? Is this way of installing the system even in line with manufacturers instructions?

Asked By matthias paustian | Dec 8 16
12 Answers

Minisplit questions

-I'm in zone 4, midwest US, and am about to buy a ductless split system for my main structure and the addition I'm finishing now. I am concerned as three of the five rooms I am putting them in are pretty oversized (~2600k btu load cooling, using the 6k heads) and the rep is saying I should go with the H2i. He said if I never need the low temp operations, the heater was worth the money.

Asked By Mike M | Dec 5 16
22 Answers

Another crawl space in the Northwest

Hello all, I have a 1150 sq ft rambler house in Fall City, Washington (near Seattle), zone marine 4c. I am currently in the process of redoing the crawl space. I have pulled the damaged and rodent infested insulation down, and removed the town vapor barrier. It seems I had some rodents that were digging past the foundation and getting into the crawlspace, ruining everything.

Asked By David Meyer | Nov 28 16
1 Answer

Lunos e2 ductless HRV system vs. ducted system

I am building a net zero house, 2000 SF, 2 stories. Can you tell me the pros and cons of the Lunos e2 ductless HRV system vs. a ducted system? The rep told me that 3 pairs of the Lunos e2 would be about right.

Asked By Courtney McCracken | Dec 8 16
3 Answers

Double interior rock wool

Working on plans for my next home. After lots of research on here and others I am considering the following wall assembly. From the exterior... wood siding, tar paper, 1/2" plywood with taped joints, 2x4 ,16 on center wall stud with roxul, uniterupted layer of 1 1/2" comfort board, layer of a variable perm vapor barrier (taped seams and such), then a layer of 2x3 installed 2 ft. on center as battens for electrical with shallow boxes , second layer of comfort board fit between the battens, drywall finish. I am in zone 5 in northern ct.

Asked By scott mangold | Dec 8 16
3 Answers

We plan to use Obdyke Hydrogap between the Hardie board siding and the Zip wall

We plan to use Obdyke Hydrogap between the Hardie board siding and the Zip wall. Will that be an adequate drainage plane? Or are furring strips also needed?

Asked By Courtney McCracken | Dec 5 16
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