Replies

1. GBA Editor
   Martin Holladay | Jan 18, 2012 10:37am | #1

   Jim,
   My only comment: be sure you have a plan to brace your walls, because Zip System R Sheathing can't be used for bracing.

   I assume you have read their installation instructions:
   ZIP System R-6 Sheathing Installation Manual.

2. 
   k8RQsvj3yc | Jan 18, 2012 11:17am | #2

   Thanks Martin - will keep that in mind. What do you think of the insulation plan?

3. GBA Editor
   Martin Holladay | Jan 18, 2012 11:23am | #3

   Jim,
   I think it will work. There may be some people who wonder if you couldn't get equivalent or better performance using less expensive (or less "foamy") materials -- but your wall assembly will work.

4. 
   k8RQsvj3yc | Jan 18, 2012 11:42am | #4

   Martin - I'm open to "less expensive/better performance", but like I mentioned in the posting last year with my original plan, the options out there are mind numbing and the choices cascade into many integrated design issues. Can you give me an example of what a less expensive/better performing option would be. Thanks!

5. GBA Editor
   Martin Holladay | Jan 18, 2012 11:48am | #5

   Jim,
   Costs vary widely, depending on local costs from insulation contractors, and the cost of framing labor. But in many areas of the country, the least expensive way to build a high-R wall is with two parallel 2x4 walls that create a 12-inch-thick cavity. Such a wall assembly is usually insulated with dense-packed cellulose.

6. 
   wjrobinson | Jan 18, 2012 12:10pm | #6

   Martin is right on but also with proper bracing and the sprayfoam your home will be braced well, insulated well and very airtight at least the wall will be.

7. 
   user-1072251 | Jan 19, 2012 01:18pm | #7

   Keep the strapping! A rainscreen won't add to your R value but may prolong the life of your siding. Its also inexpensive to buy and to install.