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12 Answers

Location of solar panels on roof

Progress continues on the North Idaho ranch. I'm planning to install a 7 kW grid tie solar system that will have 2 rows of 11 or maybe 12 panels. My roof pitch is 7:12 and my orientation is 10 degrees east of true south with no obstructions. The roof overhangs 3 feet on the section that will have solar panels. I attached a crude depiction of the installation.

Asked By Steve Wolfe | Jul 17 17
2 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
4 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
7 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).

Asked By BobTheWeekendWarrior | Sep 19 17
0 Answers

Taping OSB sheathing to ICF foam

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


Asked By Brett Greenburg | Sep 20 17
6 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

FORCE/2 Rental Locations in NY 10956 area, I am having trouble finding a place to rent a FORCE/2 for dense packing of walls.

I put up my fabric a while ago without first checking my area for a force/2. I am getting to the point where I am thinking of buying one just to do my project, which is relatively small, I a guessing a day with the right machine. All the rental places near me that I have contacted have the force/1. I am willing to travel an I am often between Albany new have and Washington DC. Please share any know rental locations.


Asked By Gregg Mastropolo | Aug 8 17
4 Answers

Structural support for windows/door with exterior insulation

I am doing a large renovation that will involve adding 3" of rigid foam insulation and I'm installing triple pane Inline Fiberglass windows that are quite heavy and I'm concerned that the methods that I've seen will not have enough structural support for the windows and sliding glass doors. What I have seen is having 3/4 plywood bucks that span the entire opening (from face of exerior insulation +/- furring strips to the face of the interior framing).

Asked By Joshua Rogers | Feb 10 11
1 Answer

I-joist blocking

Laying out shop lighting..just some 4' led strip lights. Can I use the attached method to wire my fixtures right where they need to be? I see install guidelines for I joists that say "no nailing the flange" how would these small blocking pieces be secured to the i-joist....wanting to use dense pack after all plumbing and electrical is done so I'm not wanting to create a full blocking from bottom of 2nd floor subfloor to top of 1st floor ceiling.

Asked By Inger Peters | Sep 20 17
7 Answers

Best way to plumb for outdoor shower (with hot water)?

Hi guys,

I am wanting to have an exterior hose bib that allows for hot water, so I can hook a shower up to it.

Because I am in a tiny house on wheels, my walls are only 2x4. The only product I have found is woodford hot/cold bib http://s3.supplyhouse.com/product_files/Woodford-V22CP-4-MH-Submittal.pdf

Unfortunately, even for the 2x4 model, it's 5 7/8" long. So this product would stick out on the interior side.

It's also important to note that my one piece corner shower will be on the same wall, so there is no room to come out on the interior side.

Asked By Grey Wolf | Sep 12 17
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