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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

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
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
9 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
1 Answer

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
1 Answer

Sourcing Foamglas

I'm considering Foamglas as footing insulation. Does anyone have contact information for pricing and ordering Foamglas T4+ boards in the US? I've started working my way through the contact info on their website, but I'm hoping someone may already have found the right person to talk to.



Asked By John | Oct 4 15
1 Answer

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
7 Answers

Can anyone direct me to the best information on wiring a new residence for 100% LED lighting?

I am looking for LED wiring 101 ~ What are wire gauge options, voltage regulating options and what are the things to watch out for?

I understand we are still very much in a hybrid AC/DC universe and AC has to exist for kitchen appliances, and infrastructure appliances in the Utility room, however our client wants to take the step into LED. The house is around 1600sf and one floor.

Asked By Caroline Di Diego | Apr 13 15
10 Answers

NON-Flanged (Insert) Window Replacement + Flashing

I changed out my rotten wood framed windows for all vinyl ones. The original wall was aluminum siding. I fixed the rotten sheathing, applied house wrap. Then strapped (furred) the wall with plywood. The pictures show how I flashed the rough window openings. I did NOT want flanged windows because I did not want to have to disturb the siding when the window needs to be replaced in the future (far into the futuer I hope). I see a lot of articles on how to flash flanged windows, but I never see methods for Insert (non-flanged) ones.

Asked By Alexander Sanita | Sep 28 15
10 Answers

How to release stored heat in floor's thermal mass

Years in the planning, five months in building, we are now home at last in our 1,100 sq passive home at 46 degrees North in North Central Minnesota.

Fujitsu Halcyon mini split heating and cooling.Heat load is around 26K BTU

Q 1. Am I correct assuming that I have to set the the two mini splits' thermostats at a night time temp that is lower than indoor temp before the concerete floor's thermal mass will release its heat?

Last night I set mini splits at 66 degrees -- guessing that that setting would be cooler than floor.

Asked By Randy Bunney | Oct 2 15
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