Keel Laying
Keel Laying is the traditional milestone that marks the formal start of a ship construction. Historically it was the laying of the actual keel — the backbone running the length of the hull; in modern block construction it is recognised when a defined amount of the hull structure (a minimum weight or number of blocks) is assembled on the building dock or slipway.
Keel laying fixes the ship build date, which matters for regulation: many international rules under MARPOL, SOLAS and class apply according to the keel-laying date, so it determines which version of the standards the ship must be built to.
The keel-laying date is a legal and regulatory anchor, not just a ceremony. It sets which construction standards and environmental rules apply for the life of the ship, and it triggers a contract payment instalment — so it is one of the milestones owners and yards track most closely.
What counts as keel laying in modern shipbuilding?
Because ships are now built in blocks, keel laying is recognised when a set proportion of the hull — a minimum weight or number of erected blocks — is in place on the building dock, rather than a single keel timber.