Gaetano.... seriously I wasnt putting you down and agree I dont want this to be a pissing match. I too many times over have dealt with contractors who took the liberty to make a field change base on something they did on a past job weeks, months sometimes years ago. Just because a situation is similar it couldnt be any further from the same. Each member or beam or header etc is ALWAYS calculated on its particular criteria. there is no "book" or standard. With that said Idont want to frey away from Mikes original post.
Ridge beams are nothing more than a closer for the rafters to nail to PERIOD.
Attached are some pics of ridge beams.... please note none of them are supported from underneath like a post would be. They are all simply nailed temporarily to hold them in place untill all the rafters are secured. In the last pic you can also see at the top where the two piece ridge is spliced by a simple 2x4. I am sorry to let you down but you are 100% wrong on this.
The ridge size is soley determined on the length (span) of the ridge itself and also by the rafter size and slope (the ridge wants to be larger than the cut angle of the rafter). Another example would be a truss roof. The trusses have no "ridge" they are butted together. Even when they are erected, there is no ridge beam.
