Birdsmouth joint

• abstract: In light frame construction, a birdsmouth joint or bird's beak cut is a woodworking joint that is generally used to connect a roof rafter to the top plate of a supporting wall. It is an indentation cut into the rafter which consists of a "seat cut" (the face of which rests on the top plate) and a "heel cut" or "plumb cut" (the face of which lies parallel to the supporting wall), forming a shape resembling a bird's mouth.

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