TG,
We had to replace a 10"x16" timber spanning 25 feet and supporting 12 feet of second floor because of severe spiral grain checking. The beam was a bit undersized for the load, but I don't think it would have failed if it had been straight-grained. The timber had a boxed heart, and if it was green enough to have no surface checks when it delivered from the mill, I could see how the spiral grain could have been over looked.
Regards, Chris
