I am in the midst of a major remodel in our walk-out basement. There are two large windows that have been replaced. My contractor extended the inside trim/casing by adding a 2 inch piece of pine to the window casing to accomodate the concrete block walls. I asked for this to be replaced by one piece of trim to eliminate the crevice/seam/crack created by putting 2 pieces together. He tells me this is "how it is done when the walls are thicker". I'm not convinced. Any advice?