New Addition: Patio Roof Question

[PBD539]

OVERVIEW: I am adding a patio onto the back of my house. The roof will be a "shed" design with a single slope. The ledger board that will tie into the rafters at the peak will be mounted to the wall studs after cutting away the hardi siding. The back of my house is square with a 5' recess of 15' (example: " l___-----___l "). the patio will be inside of this recess and extend outward from the house 12'. The house is two story, brick lower & hardi siding upper.
MY QUESTION IS: The two outside rafters & two outside celing joists will be up aginst the siding & brick along half of their travel. Should I fasten these to the house or treat them like any of the other rafters & joists? Also, do I flash them and use that black sealant to adhere the flashing? I have never joined new construction to existing structure before and want to make sure it is done right. I know this is long winded, but I wanted to make sure all info was given.
Thanks
Shawn

[Don_P]

Where there is siding I like to have the siding cut away leaving a 1-1/2" gap between the roof sheathing and the siding. The siding then needs to be gently pried away from the wall sheathing enough to slip step shingles up behind it, weaving the step shingles in with the shingles as you go. With Hardie you may need to punch some nails thru and caulk the holes. Once its done run down and tighten/ reattach the siding. Try hard to tuck the steps under the tarpaper housewrap so that any water that gets thru the siding is now directed onto the face of the steps and out.

Where you meet brick there are several ways commonly used. First way is to run steps up as you shingle, just like before and then run a counterflash that is inserted either into joints in the brick or into a continuous groove sawed into the brick, again about 1-1/2" up from the roof deck. I usually saw the groove with a masonry blade about 1/2-3/4 deep, pump polybutyl caulk into the groove and then slip the prebent counterflash into it. If you don't have a brake a local HVAC shop can bend metal for you.

technically structural wood should not be attached to brick veneer

Think like a raindrop :)

[PBD539]

Don,
Thanks so much for the information. This will be very helpfull in my adventure! I do have a question. What is the reason for cutting the siding back a 1-1/2" between the sheathing and the wall? Also, is it just the sheathing that needs to be held back or do I have to leave a gap between the rafters/joists and the wall?
Thanks again!
Shawn

[Don_P]

I think we missed. I mean to have the finished siding up off the new roof shingles by about 1-1/2" so that the siding is not on the wet roof. The flashing that is interwoven with the shingles bridges that gap and protects the wall, tucked behind the siding and housewrap, against the wall sheathing.

It would help to keep the framing off the brick or use treated where they touch.

[PBD539]

It makes good sence when I open my eyes! Thanks again Don.