A dap is a recess or notch cut into a heavy timber, allowing another timber to interlock with it. Timber framers use daps to lower the profile of an intersecting beam, increase bearing surface, or lock pieces together against lateral movement. The flat bottom of the dap provides a solid resting place for the mating piece.
Heard on the job
We need to cut a one-inch dap in the sill plate to house the floor joists.
Also heard as
- dapping
Related terms
Birdsmouth
A triangular notch cut into the underside of a roof rafter to seat it securely on a wall plate.
Notchboard
A sloped framing member routed or cut out to receive stair treads and risers.
Cog joint
A timber framing connection where a notched projection on one beam drops into a matching trench on another.