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7 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
56 Answers

Mooney floor

I want to put insulation on top of a concrete floor.
A layer of foam + plywood bolted to the concrete has been suggested. (By Dana I think)
While that looks an good option I've been exploring more low cost options.

What about a Mooney wall, flooring variation.
Thinking about 2x4 + 2x4, filled with blown in cellulose. Likely GreenFiber or InsulMax.

Is that a good alternative?

Asked By Tony Tibbar | Aug 6 16
6 Answers

low E

I just installed some high end french doors that came with a sticker warning 'DO NOT SCRAPE GLASS". Does anyone know anything about this? Is it some new kind of low E film, have there been long term problems with scraping low E glass?

Asked By william Goodwin | Sep 24 16
3 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
2 Answers

Condensation on plexiglass?

Hi,

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
57 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

Asked By Susan Hanway | Aug 28 16
3 Answers

Insulating underneath wood shingles underneath asphalt shingles

Hello!

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
35 Answers

Have many questions about HVAC, insulation, and ventilation

I have many questions about HVAC, insulation and ventilation, but will just start with a few. If we decide on an exhaust-only system for a new build home, does also trying to button up the envelope tight work with that type of ventilation?

We will probably insulate with fiberglass blown in at attic floor because spray foaming the whole attic would be so much more expensive. If we don't insulate at roof, do we need to install a radiant barrier at some location to try to bring the heat down in attic?

Thanks.

Asked By C Clark | Sep 21 16
2 Answers

Is HPWH reliability still an issue?

I'm seeing a lot of negative feedback on the reliability of heat-pump water heaters. Are they much more prone to problems than straight resistance heaters? If you had to choose a 50-gallon domestic model, what would you choose?

Asked By Charles Campbell | Sep 23 16
0 Answers

Rain screen detail on chimney box with brick veneer and flashing detail

Building chimney box on peak of roof for chimney pipe and plumbing vent to exit. Thin brick veneer with a rain screen detail. The lid for the chimney box is elevated 1/2" for an air gap with 3.5" down turned legs for weather protection. All good so far, but when I go to install the step flashing on the roof next to the brick and then the cap flashing over that which it's mortared into the grout line, there is now no more ventilation from the bottom of the rain screen as it has been sealed off with the flashing details.

Is this an issue?

Asked By eric Mikkelsen | Sep 24 16
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