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15 Answers

Geothermal vs. air-source heat pump

I have researching and getting quotes on hvac for a while now.. It is getting to crunch time.
Well insulated, tight house.

All three quotes include:
3 units, 3 air handlers, each zoned 3 times. Rigid Trunks and short flex runs.

option A. Carrier 18seer 25vna08... 5 stage. ( I don't like the potential harmonics problems of their greenspeed)

option B. Lennox x25 top of their line variable.

option c. Waterfurnace 7 series geothermal units. horizontally drilled ground loop.

In General questions | Asked By Dean Sandbo | Jun 22 16
1 Answer

Does this vapor barrier underlayment offgas?

Hi!

Thanks in advance for any help! Putting cork floor in a basement and need a vapor barrier. Of these three choices, does it matter which one I use from an off-gassing standpoint? I am trying to understand if these products off gas toxic chemicals into the home. The cork flooring is pre-treated so we won't be sealing it once it is down.

This one is "Bonded polyethylene" but I don't know if that off gases.....?
http://www.wayfair.com/Shaw-Floors-2-In-1-Foam-Underlayment-100-Square-F...

These two seem less likely to off gas based on description but I don't know:

In Green products and materials | Asked By Melinda S | Jun 27 16
8 Answers

Making the best of a misplaced vapor barrier

The project: an aluminum-bodied step van to be converted to a low-energy tinyhouse. It will move around once in a while, and needs to handle a range of climates.

The materials:
- heavy aluminum skin, built fairly air-tight (much tighter than corrugated RV siding)
- 4" thick fiber/paper-faced polyiso
- plywood interior panels, most likely
- a 100W heater/vapor generator that runs on potatoes and wine
- additionally heated by a woodstove when it's feasible, catalytic propane when it's not. I'm also looking into air-air heat exchangers.

In General questions | Asked By Geva edhrven | Jun 13 16
4 Answers

Lowe's ThermaTru Doors

Looking to get a reasonably priced but energy efficient entry door. Lowe's sells fiberglass TheraTru doors with polyurethane that initially seem to be around U-Value of .21 which seems pretty good for a door. They also have a triple locking mechanism.

Any pros, cons or feedback on these doors?

In Energy efficiency and durability | Asked By Peter L | Jun 27 16
9 Answers

Insulation distribution with a low ceiling; efficiency vs. comfort

Context: a 14' x 7' x 6'8 tiny house built on a step-van chassis. Heated by wood and propane. Designed for Zones 4-7. Primary occupant 5'10 or so. Insulation is reclaimed polyiso, mostly 4" with a few 2".

In Energy efficiency and durability | Asked By Geva edhrven | Jun 26 16
14 Answers

Options for replacing 2-cycle gas weedwhacker / string trimmer?

I recently replaced my gas-powered push lawnmower with a manual reel mower (Fiskars Staysharp Max Reel Mower, 18-Inch) for maintaining the grass on our small (7,500 sq ft) lot.

In Green products and materials | Asked By Robert Hallenbeck | Jun 26 16
8 Answers

Insulation/ conductivity math help, please

I recently read one of Martin's posts about (so-called) radiant floor heating.
It was exactly what I needed. The dream of a toasty-warm floor under bare feet is only a dream- unless the boiler runs all the time- either to keep up with a poorly insulated and/or drafty house- or if a well-insulated, tight house is overheated.
Instead, I'll opt for mini-splits.

In Energy efficiency and durability | Asked By Ben Rush | Jun 25 16
33 Answers

Electric baseboard — mounting questions

I am converting to electric "baseboard" heaters in preparation for a solar install in a year. I live in a cold winter climate, Detroit. Conventional practice is to mount them low, preferably under a window.

However, mini-splits are mounted high. Here, ceiling fans are uncommon, especially with reverse cycle winter use. All of my rooms will have fans. I want to mount them high. This seems to make sense, given the fan and mini-split efficacy.

In Mechanicals | Asked By Marlena Crows | Jun 18 16
12 Answers

Heat pump water heater + AC + refrigerator combo, someone?

Only wishful thinking ,

has any commercial products come up with a combo of any of the floowing items ??

- heat pump water heater ( tanked )
- heat pump AC
- heat pump heat
- refridgerator/freezer ??

I don't know why, but i think i recall looking at a product a few years ago that
comboed AC and water heater ??? can't find it anymore

what about water heater and refridgerator ?

I'd say, if use the heat generated by refridgerator/freezer pump,
would it make enough to hold up water temp in a tanked WH ??

In Energy efficiency and durability | Asked By Jin Kazama | Jan 7 13
1 Answer

Is there a way to install the vents for an attic fan, even though we have siding on the house?

Two years ago my parents had their house sided. The house had an attic fan with all the proper vents .they always use the the fa as you described it. It's great. However and this is a biggie, the siding company closed in the ventilation for the fan. They tried to contact the siding company, but the seemed to drop off the planet. Is there anything that can be done to use the fan again?????? Please help!!! Thank you.

In General questions | Asked By Gretchen Obst | Jun 25 16
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