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1 Answer

Solar hot water system with oil heat, one hot water tank or two?


I'm wondering if someone could help me. I am very new to the site so I apologize if I have missed the answer to this question in the archives.

Asked By Audrey Considine | Oct 5 15
2 Answers

Vapor barrier on DIY walk-in cooler?

Hello, I need someone to answer a simple question for. I have searched the web and gotten conflicting answers.

I'm building a 15X20 walk-cooler that will be kept between 35-40 degrees F. This is for storing poultry eggs on a egg production farm in Milton Freewater, Oregon. (NE Oregon)

Three walls will be inside the larger barn structure, which will be kept between 60-80 degrees F, the fourth cooler wall is formed by the exterior barn wall, facing west.

The design completed so far is as follows;

Asked By Mahlon | Oct 4 15
2 Answers

Any one have experience with Chilltrix equipment?

A client has asked me to evaluation Chilltrix HVAC systems:http://www.chiltrix.com/small-chiller-home.html.

It appears to be an inverter driven mini split style system that uses a chiller rather than a condenser. I am assuming that it uses and expels significant amounts of water as it does not use a refrigerant, but their documentation is not very specific.

Any feedback would be appreciated.

Asked By Carl Seville, GBA Advisor | Oct 4 15
10 Answers

Value of Phase Change materials

Our passive solar house was completed in June of this year. I designed it using principles learned on this web site and Fine Home Building magazine. I followed somewhat the Pretty Good rules found on this site and a great deal of input from the Energy Nerd blog.

Location is Bellingham, Wa north of Seattle right on the Canadian border.
10-20-40-60 insulation.
Triple glazed windows with a good solar gain. Approx 8% window to floor ratio.
Overhangs to provide appropriate shading. South facing.
Double wall, advanced framing. ACH 1.0.
HRV and a mini-split.

Asked By Stephen Carlton | Oct 4 15
6 Answers

Add rigid foam during re-roof

Our home on a barrier island 30 miles south of Wilmington, NC (close to NC/SC border) needs to have its shingle roof replaced. We’re planning on going to a standing seam metal roof.

If we know we want to eventually condition the attic, should we add rigid foam on top of our sheathing during the re-roof? Or spray foam the attic later?

If rigid foam makes sense now, what is the recommended type and thickness for this application?

Other house details
Climate zone: 3 Coastal
Built in 1947 (survived Hurricane Hazel!)

Asked By Robb Czyzewski | Sep 4 15
5 Answers

Strong odor after crawlspace encapsulation

We had our basement encapsulated in the fall last year and made it through winter no issues. They used a thick mil high quality (apparently) vapor barrier and then sprayed /fogged with mold preventative. I don't think there is any more mold - smell is not musty really and I don't get a mold allergy reaction.

Asked By jeff weikert | Jul 22 14
3 Answers

Insulation advice

Sorry to repost this ? But we are over wellmed?
Just got some prelims back and he's want to know about insulation details so they can be noted.
Zone 3,12/12 pitch standing seam roof with 5/8 plywood an clips,2 story with a option I bonus room on the third,it has a half story truss,24 on center,we were thinking about spray foamin the inside roof line but know if that the best option.
Walls are 2x6 on 24 centers,we planed on putting 1 inch exterior foam board under hardie board and over tyvek and osb but don't know if that's te best option.

Asked By Quinton | Oct 4 15
0 Answers

Ductless heat pumps and conditioned crawl space

Any suggestions for using the two together? I'm intrigued by the efficiency of the DHP's, but don't know how I can get some of the conditioned air into the crawl space without auxiliary fans or such. Thank you for your help.

Asked By Philip Joyal | Oct 5 15
7 Answers

Mini-split + heat pump water heater OR geothermal cool/heat + water heating?

Dear All,
I have read a number of articles on this forum and most seem to favor ductless mini-splits over geothermal. I believe peopel have said performance may be neck and neck while up front costs probably favor the mini-split.

However, what happens when water heating enters the equation? Some background:

Asked By Gina Jasso | Oct 4 15
0 Answers

retro insulation


I've got a 150yr old big house back house type farmhouse in Maine. Even though there was some blown in cellulous in the ballon frame construction, it's cold in the winter (exterior walls feel very cold to the touch).

I'm debating between the following for adding to the interior side of exterior walls right up against the lath and plaster:

1. Putting up sheets of foam with drywall backing (how many inches is the best efficiency/cost choice)? Any caveats?

2. Putting up a two by four frame then filling with roxul insulation http://www.roxul.com/products/residential/products

Asked By DJ Polojarvi | Oct 5 15
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