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9 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:

In Energy efficiency and durability | Asked By Gina Jasso | Oct 4 15
7 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!)

In Energy efficiency and durability | Asked By Robb Czyzewski | Sep 4 15
0 Answers

Insulating the Exterior of foundation Rubberwall and hydrostatic pressure

(Zone 5A) 2 questions really

1st - have been using Rubberwall as my foundation sealer for years and been very satisfied with it. I usually will put a layer of some insulation on the rubberwall at the time of install to protect it but also when looking for a exterior insulation job. Lately I have been wondering if there are any redeeming qualities in the green colored rubberwall material. In other words is its manufacturing toxic or bad news in any way.

In General questions | Asked By Arthur Jackson | Oct 5 15
2 Answers

Sidewall Dense Pack Cellulose - Many cavities full of scrap drywall

Hi everyone,

I had posted this on the HomeImprovement subreddit, and was directed this way.

Anyone out there have any experience with retrofitting dense pack cellulose?

I've got a 66 brick ranch home with no insulation in the walls. I'm preparing to remedy that this week. I picked up my 1200 pounds of cellulose over the weekend and I've got a reservation for an Intec Force 2 blower.

In Energy efficiency and durability | Asked By Brandon McWilliams | Oct 5 15
1 Answer

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.

In Mechanicals | Asked By Philip Joyal | Oct 5 15
4 Answers

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.

In Mechanicals | Asked By Audrey Considine | Oct 5 15
1 Answer

vapor barrier in attic?


In Energy efficiency and durability | Asked By Lucyna de Barbaro | Oct 4 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;

In GBA Pro help | Asked By Mahlon | 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.

In Green products and materials | Asked By Stephen Carlton | Oct 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.

In General questions | Asked By jeff weikert | Jul 22 14
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