Span/load beam questions really cannot be answered. You will need to have the plans looked at by a engineer. At the very least the lumber yard selling the beam may have an on-staff engineer to have a look at it.
Roof Line 30 Foot Span
Use a steel beam.. That would be code.. steel w10x15 (50ksi) I beam.
It depends on the roof load and the actual clear span. Off hand, I would guess htat you haven't given this much thought. A rule of thumb for a steel truss is one inch per foot of span or in your case 40 inches. If you want to use a steel I-beam, you can get that from a good municipal library from the steel beam institute, but you are going to need a crane to place it. Dieter in Cincinnati
big one
That really depends upon the load you need to carry and the material that the beam is made of.
I'm afraid we do not have all the information needed to amswer your question. Your safety is important, and you would be better served to discuss your needs with a engineer that can look at the whole picture.
What size steel I beam do I need to span a 32 feet garage with a floored storage above and no posts
the beam has a total volume of 60ft 3 what is the maximium horizontal gap that the beam can span
The recommended patio roof beam span according to the patio roof beam span table is typically around 10-12 feet.
The recommended pergola beam span according to the pergola beam span chart is typically around 12-16 feet, depending on the specific design and materials used.
That depends on what it is carrying. . .you definitely need to consult a structural engineer for this information, and having the original set of plans to show him will help. FYI. . .28 feet is a VERY long clear-span for any type of beam.
250 mm x 400mm