Stile

The vertical outer members of a door’s frame structure, running the full height of the door on both the hinge side and lock side. Stiles provide structural integrity and house the hardware preparations for hinges, latches, and deadbolts.

In panel door construction, stiles typically measure 4″ to 6″ wide and connect to horizontal rails using mortise-and-tenon or dowel joints. For flush doors, stiles are the solid wood or composite lumber edges (usually 1-1/8″ to 1-1/2″ wide) that provide rigidity and screw-holding capacity for hardware.

Lock stiles receive the most stress and require adequate width for lock mortises-minimum 5″ for mortise locks. Fire-rated wood doors require specific stile materials and dimensions to maintain their rating. Doors with glass lites may have intermediate stiles (mullions) separating multiple glass panels. Related terms: rail, mullion, panel door. Browse commercial doors.