Coaming

A raised boundary around a deck opening or recessed area that helps keep water out.

Hatch, companionway and ventilator coamings lift the opening above the surrounding deck so runoff, spray and water on deck are less likely to enter. Cockpit coamings define and protect the cockpit edge and may also support seating or fittings.

A coaming reduces water entry but does not by itself make an opening watertight. Height, strength, drainage, seals, closures and the vessel’s operating conditions determine the protection provided.