I am in the process of converting a small barn (25x32) into a workshop. The structure was built around 1870 and is mostly pine and hemlock with most upper level timber being 6x6. As part of a connected structure we could not jack it back to level without major issues with adjoining buildings so we took up the floor and mounted sistered dimensional plates and joists in a level plane.

Problem is that the (overhead)tie beam and a collection of iron rods that were just above head height before are now threatening to become even more annoying...

A word of explanation. The rafter plates are 6x6 with simple half lap pegged scarf joints. At some point a previous owner added several iron rods and turnbuckles in the center bay to prevent the frame from spreading. There is a rod (quite loose) from the tie beam to the ridge. They also added plates and yard-long eyebolts to reinforce the 6x6 tie beams. The tie beams enter the posts 8" below the rafter plate (leaving 2" of clear post before the tenon in plate direction). We have repaired posts and plates and provided real footings and support so that the structure is on solid ground and not likely to go anywhere.

I would propose to raise one tie beam to rafter plate height and use something like a Simpson MSTC strap tie on the top of the tie beam (and across the rafter plate and down onto the post) to provide a good tension connection and support the tie beam with a bolster or perhaps a ship's knee if I can find the material. I am concernd about a joinery connection at the post top/rafter plate as there is not much wood there as it is. It would be preferrable not to have to remove the roof (there is just room to accomplish this plan). The other 3 tie beams in the structure are or will be parts of wall structures and will be dealt with differently. As well, we will be augmenting the current roof framing (2x6 on 24" centers - and not at all plumb to boot )and providing a collar tie/ceiling member about half way up the roof.

What say you all? Does this sound reasonable or be there dragons about?