Roller Reefing

Reducing a sail’s exposed area by partially rolling it around or into a stay, foil, mast or boom.

Unlike complete roller furling, roller reefing leaves part of the sail set and loaded. Headsails roll around a stay or foil, while mainsails may roll inside a mast or boom or around a boom, and each arrangement has different shape, load and handling constraints.

As area is reduced, sail shape and reinforcement may become less effective unless designed for reefing, and excessive partial rolling can produce poor balance and high local loads. The reef must be secured through the intended mechanism and backed by a plan for jams or uncontrolled deployment.