Operating Sash Doors When the weather is ideal, welcome fresh breezes inside with our operating top sash door. The top sash can feature glass or panels, and each door is custom-built to your specifications. An integrated screen within the exterior Sea Island–style moulding keeps insects out, while weather seals—matching those in our inswing casement windows—ensure reliable performance. The sash can also be fitted with surface bolts to withstand the toughest weather conditions. For flexibility and privacy, add an interior operating panel shutter to cover the glass opening. Alternatively, our hinged panel shutters, tailored to your specifications, overlay the glass from the outside stiles and secure with a side bolt. These 1″-thick shutters feature 3/4″ raised panels on the front, matching your door, with a flat back that closes snugly against the glass.