...thanks so much for the replies..
You are most welcome! Thank you for coming to the TFG forum for your advice...
...Yes, the foundation has been completed, minus filling in gaps with concrete or anchor bolts. I think my only real reason for wanting to secure the timber to the sill plate is to pass whatever code the inspector decides to use once they come back (I think it's up for debate, as there are very few timber frame structures in this area with the exception of Old Salem)...
North Carolina can be a "funny" state when it comes to timber frames and how municipality officials "want" (or think?) they need to consider them. I was stationed there for a number of years (on and off) while in the Marines. I've been a part of and/or affiliated with several timber frame projects within the state. Vintage frames have gotten more leeway than modern built frames in a number on ways including foundation modality. With modern frames (especially if there is no PE involved in the project which is always recommended...or...an experienced Timberwright) the building department for a given municipality will often follow the path of least resistance and either not allow a timber frame at all...(less common today...thank goodness!!!)...or subject the project to "hoops and hurdles" that are not necessary...It all depends? I can state, that for both commercial and domestic, it is getting better each years as the general public learns more about the nature of the craft.
A dear friend (former student) lives in Asheville and has been operating a Tree Service ("Smart Fellers") for over a decade now. He has done a number of timber frames and is a resource if you wish to contact him.
...I have seen straps used in pictures, put in place in the gaps of the concrete block and then anchored with concrete. I thought that might be an option, but I would like for it to look 'prettier' than that. THank you, gents. I may be emailing you with some questions as I move forward. ...
I too find aesthetics (and authenticity) very important so understand the desire not to employ strapping. I can say there is no reason you need to in your build as I read it?
Hidden bolts or even (perhaps?) structural polyurethane adhesive (e.g. PL Premium) alone would more than surface to fix the PT board sill and the timber frame sill plate to the concrete well enough to meet local interpretation of IBC. If going with PT wood I would recommend (and I will only use) a thin copper shroud over the PT. I personally won't allow PT products on projects typically.
If a OPC foundation is spec'd for a project (as you have in your - again I don't use PT wood sill boards at all) and only the thin copper flashing. If a "tie down" system is demanded by local building departments the following is the format employed in such projects as yours:
1. I invoke our PE and traditional proven standards for the project. This usually (95% of the time plus) puts such issues to rest and no tie down is used and only a simple stone plinth foundation with perhaps drift pins...
2. If a PE is not part of the project and/or the effort to "push back" on the building department is not desired, then the copper flashing is laid over the OPC foundation wall with a 15 mm lip overhang. 20 mm by width of sill by 50mm White Oak, Locust, Catalpa, or related "draft spacers" are set on the copper every 2' and doubled at point loads, then the timber frame sill itself rests on these. After the sill is positioned and the "corners pulled" to square, the frame is raised upon its sill beam. At this juncture, at the corners and centers of each bay (or building department require spacing requirements?) 1/2" holes are drilled through the sill. Then, with a proper masonry carbide bit, the OPC foundation wall is drilled for a given spec'd epoxy anchor bolt system (several applicable types to choose from) and the frame is thus tied to the foundation.
Good luck and look forward to picture if you will share them. More questions are welcome too of course...!!!