Tim

that's a tall order to check. I'll likely go back sometime. I presumed it was square rule first of all because of its age (1885). And saw housings as well.

Your post-tie-strut suggestion of forming a truss works for me. In order for the walls to spread, the "arcade" posts would be have to bow considerably... the interrupted tie would pull on them, etc.

But these tall posts hold the ridge up via the major rafters, thus preventing ridge sag and the resulting wall spread, so these two factors probably keep the walls plumb. (that my take).

I noticed the open mortise only after I saw it in the photo, so not sure if ties were removed. And yes, just one peg. Didn't see any wedges. You must be thinking dovetail tenons...

The walls are pretty straight, no bow. In fact the barn is pretty stout overall. Nice building.

I noticed the "gussets" tying the rafters at the peak. I would have expected a ridge beam w/ major rafters. And I think that is a tie over the center isle in the last photo. This is the second-to-last bent of the barn.

The posts are 8x8 w/ some taper I think.

And the interrupted ties connect to the exterior posts like all crossties in the other CGs here: on top of the posts and cant past them a bit to catch the flying plates (in this case).

Have you ever seen this post style in the center isle?

More pictures here, just scroll down a ways:

http://www.tfguild.org/forums/ubbthreads...16&fpart=15