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13 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
9 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
0 Answers

How to air seal a sloped bonus room ceiling

I'm starting the process of building a new house in climate zone 4a.

It will have a "bonus" room above the great room. One area of the bonus room ceiling will be sloped as it will follow the roof line in that area. This will be one wall only and the sloped area will be approx 2' in height, approx 18' long. The rest of the ceiling above will have blown cellulose. It will be a vented attic space. Knee walls will also be cellulose insulation backed with an outward facing foil faced rigid insulation board.

Asked By Stephen Cook | Sep 23 17
10 Answers

Which long screws are really necessary?


So I know an engineer should confirm everything, and are useful in most cases ,but lets see if I can get cheaper advise and experience form others. (I have paid for numerous other required Eng. stamps).

Also this is a storage/work shop so I am not as concerned.

I'm looking for best bang for the dollar(LIKE EVERYONE) in a 6" screw for holding my horizontal furring strips on the walls. I'm in Ontario Canada, so less choice of stores willing to ship.

Wall inside -out
2 x 6 stud wall @ 16" OC.
7/16 OSB sheathing
3" Polyiso

Asked By Dave B | Sep 9 17
2 Answers

Subfloor for new covered 3 season porch?

I am planning a new 12'x12' 3 season covered porch attached to the house in far northern Minnesota. The footings are pinned to solid ledge rock, so there is no chance of this thing moving. I'm using pressure treated ledger and 2x10s joists.

The porch will be about 4' above the grade. The underneath of the structure will be protected from critters by heavy screening and a trellis. However, it will be exposed to outside air movement and temperature and humidity swings.

Asked By Steve Lenertz | Sep 23 17
3 Answers

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 rainscreen? Any comments on the rest of the detail?


Asked By Jonathan Lawrence CZ 4A New Jersey | Sep 22 17
4 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
11 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
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
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
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