Note: FYI, the TF plans will be using 6x6 and 4x6 and can carry a 60lbs/sq roof load. It was originally designed for someone in Mass and the designer was selling the plan on eBay so I bought it to build a guesthouse. Scott Stevens designed it and sells it on eBay or off his website at Grand Oak TF website. It's Timberline II plan.

I asked him if he could design me a foundation plan and he advised me to consult this with local expert but most of the expert in the area doesn't know what Timber Frame is and not know how much load it could stress on concrete system.

The plan calls for 40' X 24' but I am planning to convert 28' X 24' as a guesthouse and use 12' X 24' as garage. So the 12' x 24' obviously will be concrete slab with footing where the sill plate will be. As for the 28' X 24', I am uncertain of affordable foundation raised off the ground? I assume that "T" with blocks on top of it then fill-in is the best and "cheaper" of all?? Or anyone has a suggest?

I live in eastern part of NC so frost is really not the problem (2-3 months of winter) and water pipe is usually 14" deep. However there is a high wind code and this area calls for 120MPH but I'd like to go a bit higher for safety reason going 150 if the difference in cost is little.

Any input? Greatly appreciated and thank in advance for answering!

P.S. I should mention that I do have some good number of blocks with holes in them laying around at my father's property, down here, and few at friend's that I can collect and use.

Ken:
There are many engineers who can help you with your project in NC.
And some, or at least one of them, I believe, lives in either NC or SC. But anyhow, if you go to the TFEC (Timber framing engineering council) site there is a map there and you click on that state on the map and it will give you a name of an engineer who is licensed in that state.
They can advise you about what you'll need for foundation, footings, and connections to comply with the code in your area.

The council site is: http://www.timberframeengineeringcouncil.org/index.html

Good luck with your project.
Jim Rogers