This was a maple mantle built in a new construction home. We knew stone facia was going on the wall, so we spaced the corbels 1 1/2" off the wall. And the face frame for the recessed panels is wider against the wall to compensate for the rock. Not too shabby, the builder loved it. :) Materials and Labor totaled $700.00, i gave him a deal, he gave me two more houses. :)