Hello. New to the board. I had a question in regard to my "planning" steps on building a Pergola. It will be 10'x16'. I plan on using 4-4"x6" posts (only the corners). I plan on using 2-2"x10"x16' for the 16' span (i.e., beams) that will be bolted to the posts (I would also use 2-2"x10"x10' for the 10 foot span - bolted to the posts). I was thinking about placing a 2"x8"x10' or 2"x10"x10' in the middle of the 16' span (cross-ways), attached to the 2"x10"x16' beams. This would help with any deflection with the rafters, which will be (2"x4"x16's). My question is, will I have a deflection problem with the 2"x10"s for the 16 foot span (i.e., will they deflect)? As you can tell, there won't be a "heavy" load on the beams. Any input is appreciated. Thanks.