Tie into the end of an existing gable roof by removing existing facing boards wall siding and any other obstructions back to the first truss of the old roof.
New addition roof ridge framing to existing roof.
Re lay the shingles you removed from the existing roof.
After installing the rafters we still had to extend the porch roof back over the shed roof creating a valley on either side.
Then mount new trusses on the new addition walls.
Bed the end of each shingle in a 2 in wide ribbon of roofing cement placed 4 in.
They form an upside down v with the point at the top of the addition roof.
Tying in to an existing gable roof.
Blind valleys simplify framing to keep the porch roof framing as simple as possible we installed a structural ridge supported by posts at each end with the common rafters landing on top of the ridge.
That s a simple low cost solution that can tie in well with the main house.
In any case the structure.
Butt the first new truss against the old one.
Cut two rafters with a circular saw to the pitch of the addition roof and nail them across the rafters on the old roof.
Framing addition matching existing roof plane not sure i understand completely but from the 3d sketches it looks like you are lowering the pitch of the roof over the area where the addition is put to account for the greater width.
If you re adding to the gable end of the house the side wall that goes up to the roof s peak it s fairly easy to extend the existing roofline over the new space says curt schultz a realtor architect builder in pasadena calif.
How to tie a additions roof to existing roof roof designs to attach to existing home how to construct a roof from an exsisting shead how to attach a deck roof to existing roof how to add a roof over porch cost to tie into existing roof attache porch roof on house attach shed roof to house adding a roof to screened in porch adding a roof to existing.