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1 Answer

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
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
13 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
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
6 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
9 Answers

Condensation on plexiglass?


In fall-winter-spring, I have lots of condensation on my double-pane windows. After reading multiple sources on the Internet stating that condensation does not form on acrylic, I fastened a plexiglass sheet on a window to test. I lowered the double-cell cellular shades for the night.

This morning, I realized that the test failed - there was fogging on the bottom part (but no droplets). I guess I read the wrong sources or I did something wrong.

Which one is it?

Thanks for your help!

Asked By Marc Delisle | Sep 25 16
3 Answers

Could a heat pump unit be used to heat a crawl space that is closed in?

I'm thinking about having a heat pump system added to my mobile home. The home is about 1500 sq. ft., with a crawl space about 3 1/2 ft from slab to bottom of the mobile home.
This would help heat the floor above and allow me from leaving my home unoccupied for a time during the winter and only have the heaters keep temps around 56.
Well above 35 degrees.

Could this be done?

Asked By Leonard Klinger | Sep 25 16
3 Answers

Uninsulated flex duct: Does it lose its sound-dampening qualities?

I'm working on my HVAC material list. All of my branch lines are short and straight. I see where people suggest flex duct for these applications (if installed correctly) for it's sound dampening benefits. However, I am running the ducts inside soffits, and I want the ducts as small as possible so the soffits don't get too big. Since I am inside the thremal envelope, I don't need insulation. Insulated flex duct adds 2-4" to the overall duct size.

Asked By Clay Whitenack | Sep 24 16
8 Answers

Polyiso in bonus room

I'm starting the process of finishing my upstairs I'm located in piedmont of north Carolina. My house is 5 years old I have soffit and Ridge vents 1 dormer simple roof line 2x6 rafters . I found a deal on Craigslist for polyiso the problem is its foIL faced on both sides . My plan was to cut and cobble 3.5" pieces between rafters flush to interior of rafters leaving a 2 inch gap from soffit to Ridge vent then install 3 " polyiso on inside of rafters to adress thermal bridging then 1x3 nailers for sheet rock. Is this a sound plan?

Asked By Eric Teer | Sep 24 16
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