Although I've been perusing the TFG forum for years, I don't get a lot of time for it; hence, the lack of posts.

Regardless, I'd like to get some feedback on a question I was recently asked. In short, I've been asked whether or not a frame -- based on 6 x 6 timbers -- can be cut to support a small- to medium-sized utility building (roughly 12 x 20). For the sake of speed, pre-engineered roof trusses will sit atop the frame, so the frame will not be a bent-type design and, furthermore, it is understood that the plate beams themselves will have to be of a greater dimension ( i.e., 6 x 9).

Considering that a pressure-treated sill plate is what I would prefer to use in this design, I will probably be restricted to 6 x 6 timbers from the lumber yard and, considering that the actual dimensions of said timbers is more like 5.5 x 5.5, I'm a bit concerned about the strength of square-rule joints in such a small piece of [soft] wood.

I was taught to opt for 2" mortise/tenons in softwood, so the fact that most of the timbers in the proposed frame are actually 5.5-inches wide (on each face) brings the one-third frame rule directly into question. I'm also a bit concerned about the general lack of relish when pegging 5.5 x 5.5 frame members together, as well.

I've seen a design for small buildings where half-laps were employed for most of the connections. In this particular design, the half-laps for the posts are cut 3/4" short -- at the bottom and the top -- to allow for shrinkage of both the sill and the plate beams. Obviously, this means that half of the post bears on the sill beam, while the other half has no contact with the foundation. In other words, half of the post simply hovers above the floor and waits for the sill beam to shrink.

By the way, the foundation for this building -- a raised frame made out of dimensional lumber and connected to treated pilings -- is already in place.

I'd like to read a few thoughts on putting a small frame such as the one I've [attempted to] describe together.

Thanks for your time ...