I am building a 12x24 deck (2x10 beams 2x8 joists grade level, freestanding) and am planning on screening it in and putting a roof on. I have 2 24 ft beams as support now (4 posts each) and the deck computer program I am using says that the deck has a live load of 77 psf with just the deck structure. The program does not allow for roof planning and just adding lattice on the deck does not decrease the psf. I'm sure that framing screen (I'm assuming 2x4s are ok) and adding a roof will decrease that load but I'm not sure if it's going to be a problem. If I add a 3rd beam the load increases to 91 psf, and I'm not sure it's worth the trouble of installation for such a little increase. Also I'm not sure I want to go with the traditional shingle roof. Are there any other options for a permanent year round installation in a snowy PA? Any suggestions and advice are appreicated!