coaming

Coaming is the raised border around an opening on a boat’s deck, such as a cockpit, hatch, or companionway. It serves as a barrier to water and helps define the opening, preventing spray from entering the interior and giving a place to rest the body or lash gear.

Coamings are typically vertical or slightly sloped rims made from wood, fiberglass, or metal. In a cockpit, the coaming surrounds the perimeter and often forms a seating edge; hatch and companionway coamings frame the opening and help keep water out. Some boats have a double coaming: a lower inner rim and a higher outer lip for extra protection.

Drainage features such as scuppers or gutters are frequently integrated with coamings to channel water away from the deck. The height, slope, and curvature of the coaming are chosen to balance protection from waves with ease of movement and comfort for crew. Coamings can be part of the deck structure or separately mounted, and may be finished in wood, fiberglass, or metal.

In nautical terminology, coaming refers to any such raised border around an opening on a vessel, not only in the cockpit but around hatches and deck openings. The term is also used in architecture with a similar meaning, but on boats it is specifically associated with water exclusion and dewatering of deck areas.