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15 Answers

R-values of ceiling and walls

Zone 5a (on the border of zone 4)
Existing uninsulated concrete slab.
No basement. 2x4 frame.
A bunch of newbie questions.

http://www.homepower.com/insulation-zones
Why is the insulation recommendation for an attic so much higher than for an cathedral ceiling?
Both are the shell of the building but the attic has an ceiling under it that at least adds some insulation value. I would expect the recommendations to be closer or even reversed.

Many sites stress the importance of a high R-value to save energy.

Asked By Tony Tibbar | Jun 3 16
2 Answers

dehumidifier needed in tight house?

I've read several times that it's common for tight, well-insulated homes to need supplemental dehumidification, as the AC doesn't run enough to dehumidify the home.
As a person who is especially sensitive to humidity, I'm very interested in this.
I wonder if an equal level of comfort can be achieved more economically with a higher temp. set point but lower humidity. (In my case, Chicago area- warm and humid in the summer).

Asked By Ben Rush | Jun 27 16
28 Answers

Direct vent vs. power vent gas water heaters

A recent blower door test/audit has alerted me to the fact that my natural draft hot water heater can backdraft in worse case scenarios (range hood/clothes dryer/bath fan on). It seems to reverse back to a correct draft after a few minutes. It's only about 6 yrs old, so I hate to replace it, but not as much as I hate the idea of the back draft.

Asked By Erik Addy | Mar 8 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.

Asked By Ben Rush | Jun 25 16
8 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".

Asked By Geva edhrven | Jun 26 16
11 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.

Asked By Robert Hallenbeck | Jun 26 16
0 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?

Asked By Peter L | Jun 27 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.

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 ??

Asked By Jin Kazama | Jan 7 13
3 Answers

Unvented cathedral ceiling — insulating from above

I am re-doing my family room roof, which is a cathedral ceiling.

Since the roof is being re-shingled, I thought it a good time to remove the sheathing and lay down some closed cell foam. I have some unopened from a previous project

Everything I've read about unvented Cathedral ceilings talk about them drying from the inside. Obviously this can't happen if I'm spray in the closed cell foam onto the dry wall ceiling from above

The ceiling is 8" from drywall to plywood

Asked By Paul Buchkowski | Jun 25 16
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