Wall assembly for post frame building
![](https://secure.gravatar.com/avatar/96fddd39a43edddff919953557aeff47?s=52&d=https%3A%2F%2Fimages.greenbuildingadvisor.com%2Fapp%2Favatars%2F200x200%2Fe.png&r=g)
ve I’m designing a small three story post frame house for my family in Marine zone 4, just north of Seattle. Attached is a PDF of my proposed wall assembly. I am looking for comments on effectiveness and durability of this wall. The exterior consists of cement board over battens. I’m planning on using this for a substrate for a combination of stucco and stone. Some areas will incorporate vertical gardens and hold a certain amount of moisture. Anyone have any ideas for improvement of my Idea? Thanks.
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb1.png)
![](https://www.greenbuildingadvisor.com/app/themes/greenbuildingadvisor/dist/img/modules/detail-library/thumb2.png)
Replies
Easimonsen, your assembly looks pretty good to me.
The airtight layer doesn't need to be a vapor barrier; in fact it would be a slightly more resilient assembly if you used a vapor-permeable WRB as your air barrier (Henry Blueskin VP100 or Siga Majvest SA are good for this) to allow some drying to the exterior, but I don't think you have enough vapor drive one way or the other for it to matter a lot, considering your relatively thick layer of EPS.
You'll find 1x3 vertical battens less prone to splitting than 1x2s when you attach the cement board.
I don't know stucco, stone or tile exterior requirements so I can't help you beyond the battens. Hopefully someone else will have more information for you.
Thanks Michael, That's exactly the kind of comments I was looking for. I'll integrate the vapor permeable WRB and the larger battens in my design.