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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
4 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
6 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
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
7 Answers

ZIP Window Detail with Exterior Insulation

On ZIP's website, they have window details which appear to combine the flashing/window buck of an outie window, but it is shown flashing into a WRB (in this case the ZIP sheathing) located behind the exterior insulation.

Asked By Derrick Krienert | Jan 15 17
8 Answers

Exterior Rigid Foam Under Sheathing?

In my local area there is a green building consultant that recommends a CI panel which is basically EPS foam glued to OSB. The way this is installed would be the OSB to the exterior. Almost every house I see with exterior rigid foam in my online wonderings is covered with blue and pink XPS, the OSB sheathing is nailed directly to the studs and is completely covered with the rigid foam. This leads me to the following questions:

- Is anyone familiar with these kind of CI panels?

Asked By Joshua Greisen | Dec 8 16
4 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
2 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
4 Answers

New house build, SIPs?

New member here, we are planning to build a new house this summer and I'm exploring my options for wall systems. I plan to do the framing myself. House will be roughly 2500 sqft in Ottawa, Ontario Canada. Not the coldest place to build but not far off, and just for kicks it gets pretty hot and fairly humid here in summer as well.

Asked By Lance Peters | Jan 15 17
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