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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?

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
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.

In Green building techniques | 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?

In Green building techniques | Asked By Joshua Greisen | Dec 8 16
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.

In Green products and materials | Asked By Lance Peters | Jan 15 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
1 Answer

I need recommendations for the best way to insulate and air seal the walls and floors in in house built in 1977 in the Seattle area.

Existing walls - 2x4 @ 16" o.c.
Sheathing - 1x8 boards
Siding - 1x8 lap siding to be removed
Existing subfloor - 2x6 T&G
Floor structure - 4x10 beams 4' o.oc.
Min req'd R-value for the walls is R-21
Min req'd R-value for floors is R-30

In Green building techniques | Asked By Stewart Breslin | Jan 16 17
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