The cellar door is built using a sandwich construction. The insulation layer (polysterene) core rests within the wooden frame (mortise-and-tenon joints), and is covered by the tongue-and-groove siding panels at the front, and with a plywood panel at the back. The front siding is butted by edge pieces along the periphery, and covered by an additional frontal frame (with a horizontal brace for added support) to which we attach the hinges and the handle.
