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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.

Asked By Debra | Sep 20 17
3 Answers

Am I asking for trouble?

I may need to switch to a 2x6 load bearing exterior wall as my outer wall cannot be load bearing but had to be changed to a "Larsen" like truss. To maintain about the same total wall depth I'm considering an inner 2x6 load bearing wall sheathed on the exterior with OSB and filled with mineral wool r23 and a modified Larsen truss 2x6 wall outside. I'm envisioning the trusses as frames of 1x2 with pieces of Thermoply on one side at both ends and filled with mineral wool (about r19). Should I stagger the studs? or put them inline?

Asked By Jerry Liebler | Sep 21 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?

Thanks

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:

Asked By Lance Peters | Sep 18 17
9 Answers

Insulating basement foundation

Greetings,

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).

Asked By BobTheWeekendWarrior | Sep 19 17
1 Answer

Insulation under floor joists in a crawl space

I have recently installed a new tile floor with electric radiant floor heating over a crawlspace and am looking for the most economical way to insulate the floor. If a radiant barrier blocks 97% of the radiant heat is it necessary to install foil faced EPS on the bottom of the joists for more insulation at three times the cost?

Asked By pickaname | Sep 20 17
1 Answer

Silverboard Evaluation or Opinions?

I was watching the new Canadian show "Sarah Off the Grid" in which designer Sarah Richardson was building a new home in Creemore Ontario.. They were using an exterior insulation product called "Silverboard".

http://www.amvicsystem.com/silverboard-rigid-foam-insulation

I was wondering how this product with the added "reflective lamination" may perform or compare to other rigid exterior insulations? Do you think it may trap moisture between the board and the sheathing?

Asked By Scott Wilson | Sep 20 17
7 Answers

I am looking for the best ideas for a project for my high school Green Building class

I have been teaching a green building course to high school kids for 4 years. We design green buildings that are enegy efficient using the 3D BIM software Revit and learn all the latest construction techniques and standards. A lot to learn!
What I am looking for is a good hands on project ideas to apply all the theory and design.

Asked By tim eberhardt | Sep 19 17
6 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.

Asked By Norman Bunn | Sep 20 17
10 Answers

Dense pack cellulose roller: Where to get one?

As a fan of the dense packing method of cellulose in Atlantic Canada, I often run into a few key challenges from contractors:

1 - It's dusty (...not really when dense-packed)

2 - It's different and learning is required.

3 - Not wanting to use strapping (due to added cost) to manage the bulge at 3.5 lb densities.

The common response is to use a hard roller long enough to push the cellulose in. The problem is no one (myself included) knows where to get one? Can you please make some recommendations?

Thank you!

MB

Asked By Mattbrennan4 | Sep 14 17
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