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Community and Q&A

Cutting Off Portion of Existing Roof Overhang

CuriousGuy | Posted in General Questions on

Hello all,
I wanted to replace my shed (the structure on the right) with a new home office right next to my 400 sq ft ADU (structure on the left) that was built in the 1940’s.  I live in Northern California, so no snow to worry about and there are no windows on the shed side.

As such, how much of the existing ADU overhang (structure on the left) can I cut (saw off) without damaging the roofing integrity of the building?

Appreciate your time and comments.  Thanks in advance.


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  1. Expert Member

    It looks like the rafters are dimensional lumber, though I can't tell what the dimensions are. If they're common rafters, you can cut them all the way back to the top plate.

  2. Expert Member


    As Kyle said, there is no structural reason stopping you cutting them back flush with the exterior wall. However that overhang may well be what keeps the existing wood siding dry and in fair shape, as well as stopping water from penetrating the wall.

    Think through carefully where you cut the overhang back to. You may be able to just slip in a drip-edge and leave the rest of the roofing undisturbed if you pick the right spot.

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