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3 Answers

Do I need drywall between rafters and T&G wood plank ceiling?

I have read a number of articles about unvented cathedral ceiling design. I'm a diy guy rennovating a 1978 brick ranch in Nashville, TN. Im not sure what climate zone I'm in. By the map, I think I'm in 4, but code requirements seem to be based on 3. I think I've read just enough to get unsure of myself. I will hire out all of this work, but I want to make sure the right things are being done to optimize my insulation and not cause more problems. I know there have been several posts on this subject, but I haven't found anything that is related clear on my exact setup.

Asked By ecfelts | Sep 22 17
5 Answers

Clarification on unvented cathedral ceilling

Hello all, this is Annie. I needed some help with my roof assembly. I have tried to put this in the comment section under Mr. Martin Holladay's article about unvented cathedral ceilling but the system blocked my post. So if it cleared out and anyone has seen repeated questions I posted, I apologize here first.

I am in central Alabama, Climate Zone 3, and in the middle of building a tiny house on wheels. My roof is a very low slope almost flat shed roof (1/2 to 12 pitch) and I have decided to finish it unvented.

Asked By Maiter | Sep 22 17
1 Answer

Window Sill Detail

Attached are my "current" elevation and 3-D details for my "innie" window install. I recently added the beveled sill. Do you think I need to take that beveled sill to the front edge of the Roxul so it will drain down the rain screen. Any comments on the rest of the detail.


Asked By Jonathan Lawrence CZ 4A New Jersey | Sep 22 17
8 Answers

Install rigid foam while the wall is lying down

Has anyone tried installing the rigid foam EPS or XPS while the wall is on the floor deck and then installing the plywood over the foam overlapping foam seams before lifting the wall into place ?

Asked By susan cosentini | Jul 26 17
10 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
2 Answers

Once again, the New York Times flubs an article on green building

Today's New York Times announces an exciting new type of housing.

The article describes this housing option as:
- "eco-friendly"
- "sustainable"
- "a legitimately green option"

What's the article talking about? Homes made from shipping containers, of course.

Here is the link:

Asked By Martin Holladay | Sep 22 17
14 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
7 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
4 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
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.

Asked By JGood2170 | Sep 22 17
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