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14 Answers

How much are mini-splits really affected by altitude?

Hello -

I'm sizing a heat pump mini-split for my 20x20 garage, which has been pretty well air sealed and insulated with closed cell foam. I've had a series of installers out and the recommendations were all over the place, ranging from 12k to 18k BTU, and from $3k to $12k.

Two of the companies actually bothered to do a load calculation, and I tried it online as well - but those numbers had a broad range, too.

Asked By Dave H | Sep 22 16
7 Answers

Supplier for small registers and boots for ducted minisplit?

Hi all,

I have a completed manual J, S, D, & T. Now I have to find the different parts an pieces.

Because of the small loads in the house, the ducts and fittings are smaller than what I see in stock at the local big box suppliers. For example, I need 4x4 and 4x6 duct boots and register grilles. Where can I find those size fittings?

Asked By Clay Whitenack | Sep 26 16
5 Answers

Insulating underneath wood shingles underneath asphalt shingles


I've done my research and read quite a few relevant posts and articles here, but I couldn't find an exact match for my situation.

Legend has it that my home was built in 1876 in Philadelphia and moved here to Harrisburg via barge sometime after that. I'm in Climate Zone 5.

My wife and I are looking to build an insulated cathedral ceiling. Yes, I've read the wonderful GBA article :)

Asked By Drew Buglione | Sep 20 16
2 Answers

Does anyone use the wifi controllers on their mini splits?

Hi all,

I am a bit of a gadget geek (in addition to starting to become an energy nerd). I like dabbling in technology and home automation.

At our old house, I had a nest thermostat controlling a typical 2-stage furnace and a/c unit. I really enjoyed the nest functionality... setting up schedules, tracking usage, turning things off/on while on the road. Also, we lived in an inefficient house, and paid a lot for heating and cooling, so I was always looking for ways to raise/lower temperatures when we were out or sleeping, or any other ways to adjust the usage.

Asked By Clay Whitenack | Sep 26 16
15 Answers

Quest for EPS

Finding extremely limited offering of eps rigid insulation in my region (upstate ny, north of Utica).
In my manufacturer search I found a product made by Cellofoam called Polyshield. They describe it as a sheathing product and it's eps with polymeric facers on both sides added for strength.
Is anyone familiar with this product?

Asked By Daniel F. Vellone | Sep 20 16
0 Answers

Do I have an issue?

The weather is my part of Zone 3 is still pretty hot (90s during the day with a cooling trend into the upper 80s). I noticed that my two year old air-source heat pump is struggling a bit to keep things comfortable. The thermostat upstairs is set for 77 degrees but the temperature is hovering around 81.

I also observed some wetness under my outdoor unit as well as some similar signs of water in the pan under the air handler. What do you guys think? Am I low on refrigerant? What might cause that?

Asked By Steve Knapp | Sep 26 16
0 Answers

Video that aired on PBS: best practices for flange at bottom of window?


This is a video (link below) from the MN Building Performance Association, which aired as a half-hour special on PBS here in late 2015, I believe.
I am wondering if I'm misunderstanding something about proper flashing at the flange at the bottom of the new window that's being installed here. About six and a half minutes into this video, the installation gets going. The installer flashes properly before install, which I believe was the point of the new install, but then also tapes over the bottom flange. Is this correct?

Asked By Minneapolis Disaster, 6B | Sep 26 16
1 Answer

Bubble Insulation - Double Wall

Is double wall bubble insulation more effective than normal bubble wrap for insulating windows. The following is a link to the type of bubble wrap I am talking about:



Asked By Rachel Glube | Sep 26 16
0 Answers

I'll be speaking at the EEBA conference tomorrow

GBA readers in Texas may be interested in attending the annual conference of the Energy and Environmental Building Association (EEBA), which starts tomorrow in Frisco, Texas. I'll be giving a presentation there tomorrow morning on cathedral ceilings.

EEBA is a great group -- they have been promoting energy-efficient construction practices since the 1980s. I hope to see some GBA readers there.

For more information, check out the conference web site.

Asked By Martin Holladay, GBA Advisor | Sep 26 16
4 Answers

Sanity check on energy efficient window pricing

I'm pricing out energy efficient windows, and am wondering if the quotes that I'm receiving are typical. I'm looking at white, triple glazed, low-e, argon or krypton filled fiberglass new-construction casements with no grids. I've received quotes from two Canadian manufacturers that are both $47/ sq. ft, uninstalled. Does that seem in-line with other people's experience buying windows?

I'm aware that vinyl windows would be cheaper, and that double pane windows probably have better ROI. Having a firmer idea of pricing will help with that math for my house.


Asked By John Ranson | Sep 22 16
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