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0 Answers

Northern Michigan un vented, un air conditioned Cabin roof design.

Northern Michigan un vented, un air conditioned Cabin roof design.
After reading several articles, opinions and Blogs I have a better understanding of the moisture vapors that exist and the problems they can create in walls and especially the roof. But I’m a little unsure of the proper design and construction for my great lakes, shore line cabin roof design. I have detailed my current plan below. Could please you give input as to where my design plan is OK or deficient in proper vapor management for this environment and situation.

In GBA Pro help | Asked By mike bard | 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

In Energy efficiency and durability | 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...

In Energy efficiency and durability | 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

In Energy efficiency and durability | 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?

In GBA Pro help | 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.

In Green products and materials | 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?

In General questions | Asked By Linda Walker | Jan 16 17
0 Answers

Cold Access Room - Gaps in Air Barrier

** Re-posting to the proper Q&A category **

Hi -

In Energy efficiency and durability | Asked By Joe Duchek | Jan 16 17
0 Answers

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

In GBA Pro help | Asked By geoff summa | Jan 16 17
23 Answers

New earth sheltered PAHS construction

I would like all opinions regarding my new home construction project. I have a full 3 days experience learning Sketchup and have managed to put several ideas on paper. Please review my plans...and pick holes in them :). I don't guarantee to change my mind, but I do promise to research varying opinions thoroughly and supporting data would be appreciated.

Assumptions:
Mixed humid climate Missouri 39 deg latititude
CoMo HDD 5173
CDD 396
Sunny days 195
Humidity ave 70% 83% AM, 56% PM
111 days rain for 46"/yr
10 days snow for 14"/yr

In Plans Review | Asked By Laurel Davison | Nov 28 16
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