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4 Answers

Polaris vs HTP Phoenix for hot water and radiant heat

Looking at using either of those products for both hot water needs and heating (with coil/air handler) in a 3000 sqft house (slab on grade, 2 story, in Southern Ontario).

It looks like 70000btu would be sufficient, but I am wondering about the pros and cons of each tank. already know most features of each product, so I am mostly asking about anecdotal reliability issues with each brand (e.g. igniter issues on the Polaris, which may have been fixed by now).

Regards,

MT

Asked By Mai Tai | Jan 16 17
0 Answers

Renwik, Abe, Zapotek and Altus Canada

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Asked By Suguttuh Suguttuh | Jan 17 17
8 Answers

Construction Docs, quick review please

It's been a long journey but we're at the stage to begin construction in the next couple months. My architects did a stellar job combining our aesthetic vision with green energy design. For my own peace of mind I am hoping to have the experts here take a look at the construction details. Let me (and my builder, who will be dropping in on this thread) know if you have any major concerns with the construction details. The house is in 5A, oriented East-West (roof slope facing south). There is a wrap around porch, a root cellar beneath one side of the porch, and a walk out basement (south side).

Asked By Clara Kim | Jan 16 17
0 Answers

Fiberglass and Cellulose performing differently in attic

In our vented attic, we specified 18" of blown-in cellulose. In one particular location, the insulation contractors were called back to redo an area that was not covered. When it got cold outside, I noticed that the ceiling in that area was noticeably colder than in other areas. Suspecting that the insulation contractor didn't actually fix it, the builder and I went to the attic today to check. They had attempted a fix. Instead of putting cellulose in the problem area, they had installed fiberglass batts. The batts looked to be about the same thickness as the cellulose.

Asked By Reid Baldwin | Jan 17 17
1 Answer

How should moisture/vapor wetting and drying be considered in this situation?

Details:
- Climate Zone 6, Marine setting
- Stand alone garage(1970's) to be converted to an overflow guest house w/ full bath no kitchen.
- Guest house to be used in summer only.
- Existing structure on a floating slab w/ no vapor barrier beneath, sitting poorly drained soils.
- 20' by 16' area w/ cathedral ceilings, 2x4 walls and 2x8 rafters
- 20 mil vapor barrier to be installed over slab (seams taped), may not be able to extend under existing perimeter walls.
-2x4 sleepers laid flat over 20 mil VB
-1 1/2" xps fitted between sleepers

Asked By geoff summa | Jan 16 17
5 Answers

Mineral Wool R-value by temperature

Does anyone know if there is any information available that shows the performance of mineral/rock wool by temperature?

Buildingscience.com has this for polyiso:
https://buildingscience.com/documents/information-sheets/info-502-temper...

I am wondering if there is something similar for mineral wool.

A few other links I have found -
http://www.greenbuildingadvisor.com/blogs/dept/musings/bold-attempt-slay...
http://www.energyvanguard.com/blog/59419/Big-News-The-R-Value-of-Insulat...

Asked By Nathan Scaglione | Jan 15 17
8 Answers

Vapor Retarders/Double Air Barriers

May I ask to ensure we haven't missed anything in thoughts on building our home. I was under the impression we would use Closed Cell Spray foam for the entire assembly, but my husband is now thinking Open Cell for the above grade walls. Will these assemblies work?

Unvented Cathedral Ceiling
Metal Roof/Air Gap/Asphalt Felt/ZIP Roof Sheathing/Closed Cell (still negotiating the amount)/Back Venting/USG Ultra Light Drywall

Vented Unconditioned Ceiling

Asked By Bridget Lamberson | Jan 15 17
8 Answers

What to do with torrents off the roof?

Zone 4A, East TN, annual rainfall >50" and downpours can be significant. Upslope lot.

Downspouts will tie into 4" pipe to daylight, but then what? Seems responsible to NOT discharge it down the driveway. But if I discharge it onto the slope it would soon create a local grand canyon.

There will be a 3' garden wall to provide a level grade in front of the house. The 4"gutter drains will exit through that wall in two or three places.

Any tried and true remedies?

Asked By David McNeely | Jan 16 17
16 Answers

Passive house exterior door for reasonable price?

Has anyone come across an exterior door that provides good insulation and beefy frame that's worthy of a super insulated home but comes at a reasonable price? Any suggestions would be appreciated.

Asked By Matthew Michaud | Feb 4 13
1 Answer

does part of attic that covers deck need to be insulated to prevent frost buildup?

the attic over the rest of house is insulated with vapor barrier and doesn't have frost buildup. What needs to be done to prevent frost in attic area over open deck?

Asked By Linda Walker | Jan 16 17
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