Where could I go about finding the maximum safe span of a pane of glass for a specific width?
I.e. say you had two rafters, X meters apart, with glazing bars, supporting a pane of toughened glass (arbitrary height) 4mm thick along two edges; how would I go about finding, or finding the information to help me calculate, an appropriate maximum value of X?
(In order to determine whether a given design provides sufficient support.)
Best Answer
You still have too many unknowns to make such a calculation, e.g.
The above loads will totally depend on whereabouts in the world you are installing said glass.
For total peace of mind (and most likely to cover yourself legally) you really should hire the services of a a qualified structural engineer to perform such calculations.
Rule of thumb, back of a cigarette packet calculations tend to only get people into trouble further down the road.