How do you calculate the size of beam needed for the cantilever beam in hammerbeam construction?

Answer 1

Calculating loads on roof trusses involves the consideration of a number of variables. That's what engineering classes teach. There is no slam dunk formulae. But we can look at some of the variables. By the way, though the hammerbeam cantilevers out from the eaves, it is supported underneath. What's the static load the wooden truss will experience? What dynamic loads will have to be figured in? You'll have to measure the heck out of everything. Unless one wants to reinvent the wheel, the wise person would go to the manufacturers of wooden trusses and look though their offerings to see what works where. It is doubtful that they will let an investigator use their software, but they will provide some general answers through their applications guides. There are engineering packages (software) that provide "shortcuts" to finding answers to problems like this, but they cost. Some schools and most universities have one or more computer applications where the legwork is done and the investigator only has to input his requirements.