Hey Tim,

Good to bring that up for his research. Many contemporary examples being built in shops today would benefit from those tension cables, as many "hammer beam trusses," are not designed well enough (in reality) to endure over time. You can achieve a true HBT but you really must be familiar with this type of truss assembly, applied roof diaphragm loads and there tipping (over through) effect on the wall diaphragm.

Those that don't need a cable tie to be enduring are typically other types of trusses designed into a hammer beam "arch," which is really what we are talking about.

If you get the roof pitch steep enough, the timbers heavy enough, and the joinery designed applicably, you get a "hammer beamed arch."

Below is a good read, and as we progress, I am sure others will suggest more. It would be nice if we have a good bibliography on this subject by the end of the discussion. I would also be wonderful if Joel web publishes his paper.

Regards,

jay

Roof trusses pp 1006-1020; (but the good stuff starts on page 1013 for this conversation.)

The Architects' and Builders' Pocket-book: A Handbook for Architects, By Frank Eugene Kidder orig. 1885 14th ed 1916

http://books.google.com/books?id=e1swAAA...uss&f=false