Pergola beams and rafters for sale right here at Plastic Lumber Yard. Rafters create the “roof” of your pergola. We recommend 1 1/2 ft spacing center to center. You will need rafter brackets to connect your rafters to your beams. 1 per every intersection. You would also need #8 x 1′ screws. 4 per bracket. If you cannot find what you are looking for please call us.