beam loading for porch196 span
 

beam loading for porch:19'6" span
i am building a roof over a deck to screen-in. due to the form of the deck, supports are to be 19'6" apart and a beam is required for that span. the beam will carry a distributed load and a point load from two different roofs. [point load is from the support of another beam] at 30psf load for my area, i calculate that (3)2x12-20' will carry the load with a deflection=0.7 inch. [with l/240=0.975].
my questions are:
(1) will a point load be allowed?
(2) can i add assurance with a king post truss and metal tensile members? this type of truss appears simple to site-build. any recommendations on truss details?
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if the wood beam has strength enough and small deflection, i don't see any need to go for a truss.
respect the point load, the main issue is if the loading roof stabilizes enough both the loading and loaded beams, because otherwise separate specific bracing would be required. with a column loading in the beam that would be a necessity, but it is unlikely such is the case when what loads is a beam.
if you doubt, add x bracing in the plane of the roofs to inmovilize the point load point.