Thank You Dick,
If one were to use an R of 1 it would be as if you were designing the timber frame to respond to an earthquake wholly in the elastic range. It would assume that the frame has no strength beyond what the NDS and your research assumes is safe. The lowest R value published in the Code is 1 1/2 which is for "ordinary plain masonry shear walls." This has a low R value becuse this system has little strength, ductility and ability to absorb energy beyond what is deemed safe for static loads.
This being the case, would you feel comfortable designing a timber frame using an R value of 1 1/2?
