Expert: Dave Johnson - 6/24/2008

Question
Hello I am planning on building a patio cover attached to the existing roof.  To paint a picture the existing roof slopes down along where the patio cover will attach. The patio will be pitched. which means each side will attach not to far up the roof but the middle will be attached higher up the pitch of the roof. Anyway the problem I cant seem to get a very clear answer about is how should I go about the actual attachment. Maybe i am being paranoid but i am worried about the weight being directly on the roof even if i use a header along the existing roof seems like it would be a lot of weight. Oh the dimensions of the patio cover is around 24 feet wide (along the house) by 18 feet (out from the house). going to use pine beams and posts. One individual suggested cutting into the roof and attaching a support up from the exterior wall.  please any help is much appreciated. thank you.

Eric

Answer
Hi Christopher,

There will be no problem with your roof framing if you use a cleat along where your rafters hit the existing roof. (they will be along where the valley will come). I'd use a 2"x8" or wider to attach the new rafters to.... There will actually be less weight than you think on the existing roof, most of it will be on the new frame.

Best of luck,
Dave