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14 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).

Asked By MichaelBa | Sep 21 17
3 Answers

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
8 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

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
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!

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.

Asked By Norman Bunn | Sep 20 17
7 Answers

Typar vs Zip

I was thinking about using the Zip R system sheathing on my house - removing old clapboards, insulating the wall from the exterior and then installing the ZIP R. I just attended a seminar with a Typar house wrap rep who basically said Zip was no good - is not surfactant resistant and not much more that felt paper glued to OSB. But of course this is coming from the Typar rep. Any thoughts on the pros and cons of each?

Asked By Michael Mohr | Sep 13 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.

Asked By user-6921457 | 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.

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?


Asked By Brett Greenburg | Sep 20 17
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