Lay-Up / Laid-Up

A condition in which the unit is taken out of service. One of the key considerations in the early planning of a lay-up is its expected duration as this will affect what measures need to be taken. There are two lay-up conditions commonly referred to in the shipping industry:
Hot Lay-up – This is typically for a period between 1 and 12 months. A reduced crew, normally below safe manning levels, will remain on board to conduct necessary maintenance and keep some of the ship’s machinery in operation, as the ship will normally generate its own electrical power to energize important ship systems. Ships in hot lay-up will typically require a short time to prepare for reactivation or reinstatement, but in some cases drydocking may be required.
Cold Lay-up – This is typically for a period of more than 12 months. A minimum amount of maintenance is carried out during the lay-up and power is either supplied from shore or by a deck-fitted generator. A minimum number crew remain on board to protect the vessel from the risk of fire, flooding and to maintain the mooring, although sometimes an external lay-up crew is employed instead. Ships in cold lay-up take much longer to prepare for reactivation and often require drydocking.