I am building a detach garage with a 32' Long by 16' wide patio roof. I'd like to place 3 posts which would drive a 16 beam span. Was wondeing what size beams I would need. It is in S. Texas so no snow load. Rafters will be 2X8 Cedar. Patio roof will have bead board and 30 yr asphalt shingles. It appears weight on the posts will be minimal. Any idea of the size beam I will need for these spans? Most references that I've turne up have been for home roof beams.