I am looking to build a covered patio structure. This is going to be replacing a pergola where all of the beam and purlin members are rotted. The vertical support structures are 6 x 6. The main part of the structure will be approximately 19’ x 14’. The bottom of the posts have a stone like structure around them that will now get a concrete cap for seating. I am thinking of wrapping the columns with 2 x material to make them look heavier. I am thinking the main beams will be 6 x 12 or multiple 2x material glued and screwed. I was thinking the rafters could be 4 x 6 timbers at 4’ o.c. Because the roof decking is going to be 2x6 with plywood on top of that, I can’t see if that rafters framing spacing is acceptable. I plan to have collar ties at each of the rafters and a vertical member at the open ended rafters. I am not sure if I should have steel connections or wood straddle along side the 6x12 beams with the added vertical members. #home