Patio roof to house attachment question

mobilemike · 09-22-2008, 05:22 PM

Hello. Great site with lots of great info.

I am an amateur carpenter with some experience in framing, decks, and roofing.

I am planning to install a 10' x 32' back patio cover on my house. It will have 4x4 uprights, 2x6 header, 2x8 ledger, 2x6 frame, and a preferably a tin roof.

I am pondering how to attach it to the house. The house has a hip roof. The lower edge of the facia board at the house is 7' from the slab.

Option 1 and the one I prefer is pulling off the facia board, installing a 2x8 ledger board using one 3/8 x 6" lag bolt through the ledger and into the ends of each of the house rafter boards. I would then butt the 2x6 patio rafters into the ledger with joist hangers. I would also butt the patio rafters into the 2x6 header at the outside end of the patio with joist hangers. This would give me 7' of headroom at the the house, and 6'6" of headroom at the outside end if I drop the roof 6" for runoff.

The small bump in areas where the roof line is recessed would be framed in behind the ledger and plywood and shingles will cover them, extending the existing shingled roof to the ledger.

I would tar paper over the joint where the ledger meets the house, and then use flashing under the last row of house shingles and extend the flashing either 12" or 18" out over the patio tin roof.

We get quite a bit of rain here, but no snow.

I realize other option is going up and tieing into the house roof, using plywood sheathing, tar paper and then shingle the patio roof.

I would rather use the tin roof option. In your collective experienced opinions, is my plan workable or is it a complete mess?

Do you have any suggestions

Thanks for any help.
Mike

glennjanie · 09-22-2008, 10:55 PM

Welcome Mike:
Thanks for the pictures; it makes it so much easier to see what you are doing.
My thought is, since you are roofing in the whole area, why not tear off the two little porticos over the doors, make a continous facia and a level soffit. Then you could put the joist hangers directly on the facia board (right at each rafter end) and avoid the large gap between the roofs while saving another header board.
Glenn

inspectorD · 09-23-2008, 07:31 AM

I would go for the roof tie in. It will make the wayer run off the roof easier, and let you use the same type shingles to match the existing roof. They will also last longer than a roll roof which really only lasts 7-10 years . Unless you go with a rubber roof.

It really is just as easy to remove some shingles. To mess around with a poor facia connection at different height's where the ledger board will attach will be a waste. Look at you pictures and you may get a visualization on what I am saying.
Plus you must get high winds also. Make sure your connections at the posts to the ground are good, or we will see your porch on a video come hurricane season.
Good luck with it.