Attaching rafter header over siding?

[dynamorph]

I am building an enclosed porch and just now attaching the rafter header to the house. The current siding is wood shingle. It will make a mess of the shingle above and below to remove a row to attach the header. Can I just nail/bolt the header right to the siding? Behind the siding is

1/2" ply and then upright 2x4's. I plan to used galvanized 4" nails and try to hit as many of the 2/4's as possible.

Is this ok to do? My guess is that the rafter header is not bearing a big amount of weight even under snow load, but rather the weight goes down to the beams on the front of the porch, and pushes back against the side of the house, rather than directly down on the rafter header.

[Jim R]

Uh...I don't think you're going to get points for 'trying' to hit the studs. You really should cut away the shingles, install flashing and - if through bolts into a rim joist aren't possible - put long lag screws into the studs.

[Colbyt]

I agree with Jim. You will have to remove the siding above anyway to get proper flashing for your roof. Why not do the whole project correctly?

Colbyt

[andersonpalmer]

I also agree about the flashing, but you can preserve the siding below the roof by tacking your header boards to the wall with 2 or 3 nails in each board (leave heads stick out). Run a pencil along the bottom of the boards. Remove the boards and take a circular saw and set the depth the approximate thickness of the siding. Then carefully follow the line. That way you can preserve the siding below the roof and only have to remove the stuff above. You will have to apply flashing somehow, and siding removal is the only way.