This is the simplest solution a single slope that s attached to the original house at the high point and slants down to the outer wall of the addition.
How to put a addition on a roof.
To tie into the side of an existing roof put a new roof truss on the walls of the addition brace it upright then snap chalklines on the shingles to mark the center line of the new roof valleys where old and new roofs will connect.
Shingle the addition roof letting the new shingles fold through the valley center and onto the old roof deck by at least 1 ft.
Kick it or keep it.
Re lay the shingles you removed from the existing roof.
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Bed the end of each shingle in a 2 in wide ribbon of roofing cement placed 4 in.
Up from the valley center.
The next question is what to do with the existing eave under the new roof.
If the addition s roof mimics the look of the existing roof lines it won t stick out as an obvious add on.
It also helps to copy the pitch of the existing roof since it likely takes important.
Take careful measurements to determine how many trusses you will need.
Choose a roof pitch 3 12 and roof structure 2x6 this places the new roof on top of the existing roof.
It s easy for the contractor to build and easy on the homeowner s budget says schultz but it makes the new space look like an obvious add on.
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