Re-creation of shed

On our farm there use to be a timber frame 2 story shed. It burned down in the 70's. The one they rebuilt is a simple stick framed single story. I would like to rebuild it as a timber framed building. I posted a while ago about building a pavillion but since have decided a shed would make a better use of the timbers that we already cut.
On this site is the sketch-up model of what I came up with so far. I am having some slight issues with getting everything to line up perfectly and a few of the tf joints I have to still work out. The walls that the frame is sitting on are existing.
Chris's page
The sketchup file is New Middle shed127

Any input would be appreciated

I am not looking for load calculation information. I am just looking for feedback on the general frame design good or bad.

Thanks

Chris

We replicated a “Shed” with almost the same footprint some years ago for the Canterbury Shaker Village. In that instance the framing was based on existing photographs and the others buildings in the village.

The structural ridge suggests you are not holding yourself to such constraints, and are free to do anything you wish.

All the same I would drop it. (That though may be personal bias, I hate them) It this instance it limits use of the attic space greatly.

I'd raise the ties a little, and join principal rafters to them , a principal purlin to that, full length cogged over it in a higher plane, with the common rafters cogged over it, and the roof plane in yet another layer.

Unless the girt height is situated to accommodate a tractor I'd drop it a little, and I would again go with layered systems. Cogging the joists over the girts, and raising the connecting girts to the same height, thusly eliminating the three and two way connection in the posts.

Structural elements needn't line up, particularly in an out-building. A frame is often all the better structurally and more pleasing to the eye, when they don't.

Use the frame as a teaching exercise for yourself, and play a little.

Thanks for the input Will. I so far have not been able to find any pictures. I am still working on that. I have been just going on what my dad and uncle remember. They know they could back a Farmall MD with a loaded hay wagon into it. We still have the tractor so that is what I am baseing the lower level height on. On the upper level they remember having to duck to avoid hitting the tie beams. We have two other timber frame buildings. The barn which was built in 1853 is canted queen posts supporting principal purlins with common rafters. There is also another shed that was built sometime later with recycled beams from a mill close by. It has straight queen posts supporting principal purlins with common rafters. Other than the space limit in the attic what are the issues with a structural ridge? I didn't think the two and three way connections were ideal but I wasn't sure how else to make it work.

Thanks again

Chris