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3 Answers

Climate Zone 3-strategy for venting or not venting a small attic kneewall space?

Climate Zone 3. I have a Finished Room of the Garage (FROG) with kneewalls that has wood paneling on the finished side. The paneling started to show signs of moisture issues. I removed the paneling and found no mold in the space but elevated moisture (22%). R13 insulation with vapor retarder on warm on winter side is present. There is not much room between the kneewall and the exterior wall of the reverse A. Essentially a double 2x4 wall is it.

In GBA Pro help | Asked By JGood2170 | Sep 22 17
2 Answers

Has RMI finally come up with a good home energy efficiency rating system?


I've said for years that a raw HERS score is useless to an average homebuyer.

In General questions | Asked By Kevin Dickson, MSME | Sep 22 17
16 Answers

How to flash window trim below window

Hi guys, I have been reading a lot about flashing and according to Hammer and Hand, these are the locations that need flashing:

Flashings should be installed:
1. At all horizontal joints between different exterior finishes unless the upper finish overlaps the lower finish.
2. At every offset in cladding, changes in cladding substrate, and at all penetrations (horizontal transitions between siding, stone, brick, tile, or stucco).
3. Where stresses can be concentrated (such as at the rim joist/foundation joint).

In Energy efficiency and durability | Asked By MichaelBa | Sep 21 17
2 Answers

Shed roof attachment to a wall with exterior insulation

Good morning all,
I'm interested in your thoughts on the detail of how to attach a roof system to a side wall with the following design details:
2x6 framing with dense-pack cellulose
1/2" ply
soletex mento WRB
1.5" roxul comfortboard 80
3/4 furring strips
lap siding.

for the decks and porch I'm hoping to use "Maine Deck brackets"
I'd prefer not to break the exterior insulation shell.

thanks in advance!

In Green building techniques | Asked By Thomas Gibson | Sep 21 17
7 Answers

HVAC sizing disparity relative to HERS report

My HERS rater shows heating load of 39,500 Btu/hr and a cooling load of 22,600 Btu/hr on a high performance house I plan to build. This includes 1000 sq ft of basement, 2500 sq ft on the main floor and 800 sq ft in an office/loft area. R40 ceiling, R20 walls, R5 basement and crawlspace wall insulation plus serious air sealing (3 ACH or less).

The HVAC quote shows no system in the basement (it will be finished by me after construction), 3 tons on the main floor and two tons for the loft with all duct work in the conditioned space.

In Mechanicals | Asked By Norman Bunn | Sep 20 17
3 Answers

Cut and cobble - basement ideas?

Hello all,

I'm located in western Washington, zone 4 marine, and we're working on our early 1970s split level. When we purchased the home last year we ended up needing to put in a sump pump and interior footer drain. Since then, we've been monitoring the walls and relative humidity. There's been no new evidence of moisture and later this month we'll be installing a new heat pump and plan to use the dehumidifier function.

In General questions | Asked By Bill Cooke | Sep 19 17
2 Answers

Toughest vapor barrier for floor of crawl space?

We're building a new house, and plan to create a sealed conditioned crawl space. We want to be able to access the space regularly, to inspect for leaks and store a few items. Which vapor barrier would be better able to hold up to regular traffic? We'll probably put a layer of coarse sand underneath it. Unfortunately, a concrete rat slab is out of our budget.

In General questions | Asked By Debra | Sep 20 17
1 Answer

Taping OSB sheathing to ICF foam

Does anyone have experience with an effective tape for sealing OSB sheathing to the ICF stem wall foam?


In Energy efficiency and durability | Asked By Brett Greenburg | Sep 20 17
5 Answers

Pros - How Would YOU Build?

This question goes out to the pros on this site; those who are builders, building science aficionados, or some mixture of the two.

Many folks, myself included, come here with some vague ideas of how they think they would like to build and then post their ideas asking for advice. Instead of starting somewhere and then working backwards, I'd like to know where the pros would start. So here we go:

In Energy efficiency and durability | Asked By Lance Peters | Sep 18 17
9 Answers

Insulating basement foundation


I have read a lot on GBA and a few other trusted resources online and am still not clear. I have an unfinished basement below grade in zone 4 (Minnesota). House was built in 2015. Builder sprayed a black coating on the poured concrete foundation and then applied a 1.5"-2" thick rigid foam insulation to the exterior of the foundation before backfilling (completely below grade basement).

In General questions | Asked By BobTheWeekendWarrior | Sep 19 17
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