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40 Answers

Best exterior wall design within standard 2x8 dimensions

I have been reading several of the GBA posts and articles and I don’t seem to locate the answer to my question so I wanted to drop you a line by email.

I am located in Saskatchewan, Canada and currently have a house under construction that is well under way. That being said I won’t over complicate it with detail but the house is not a high efficiency design and I am not and don't pretend to be knowledgeable on a lot of points that are covered on GBA.

Hhowever, this is what i have

Construction detail:

Southeast corner of Saskatchewan, Canada 15 miles north of North Dakota

Asked By chad online:) | Feb 21 16
3 Answers

Insulating the underside of a concrete deck?

I have a 2-story garage project where the lower level is built with ICF walls...R-25....and PEX radiant heated floors with an R-10 underslab insulation but the ceiling consists of the metal concrete pans and +/- 8" of concrete and rebar. Assume that space above is unheated.....it might also get insulated and heated from time to time when the homeowner needs to do automotive work.....but in general it will be unheated.

Asked By JONATHAN SCHOLL | Jun 27 16
3 Answers

Closed-cell foam versus thermal bridging

I have read several of Martin's articles and reader responses regarding the benefits of using closed cell spray foam on the underside of unvented roof decks. Because it is vapor impermeable, you can spray the underside of the roof without fear of vapor migration to the cold sheathing...so long as it is the proper R-value..... which would then cause rot over time. That's all good. In a cathedral ceiling or gable end wall, what happens to the rafters or studs which cannot be encased in the foam due to the need for drywall?

Asked By Jonathan Scholl | Jun 27 16
5 Answers

Two layers of insulation or one?

We are installing 2" of Hi-load XPS rigid foam insulation under a heated slab in zone 4a and we have the option of doing 1 layer of 2" insulation or 2 layers of 1" insulation. I'm wondering if there is an advantage to overlapping the seams or if it's inconsequential at the end of the day. We will be taping the seams.

thanks,

bigern

Asked By Big Ern | Jun 27 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?

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".

Asked By Geva edhrven | 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.

Asked By Ben Rush | Jun 25 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
2 Answers

Upgrading a crappy HVAC setup

My wife and I are in the process of purchasing a new home in Northern NJ. The home was built in 1986 with forced hot air heat and withOUT air conditioning. Air conditioning was added later.

As a result, the house has two sets of ducts. One set feeds heat to both floors from the basement. The other feeds conditioned air to both floors from the attic - but there are too few ducts on the first floor for the A/C to work well for that floor.

The furnace uses oil and is likely nearing the end of its life. Also, the house has a pellet stove.

Asked By Matt Culik | Jun 24 16
8 Answers

I am thinking of an unvented cathedral ceiling

Hi. I am thinking of an unvented cathedral ceiling. Living in Hazelton, BC (Zone 4A, I believe), and would like advice on my proposed insulation plan. Staring from the underside: vapour-retarding paint; sealed gypsum board; 3/4" strapping; 2" or 3" Roxul board.

I would like to achieve at least an R50.

Asked By Mike Tomlinson | Jun 24 16
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