Timeline overview by size
| Vessel size | Design phase | Hull construction | Outfitting | Sea trials | Total |
|---|---|---|---|---|---|
| 30–45m | 6–12 months | 8–14 months | 8–14 months | 2–4 weeks | 18–30 months |
| 45–65m | 10–18 months | 12–18 months | 12–18 months | 3–5 weeks | 30–42 months |
| 65–90m | 14–22 months | 16–24 months | 16–24 months | 4–6 weeks | 42–60 months |
| 90–120m | 18–28 months | 22–32 months | 22–32 months | 5–8 weeks | 56–84 months |
| 120m+ | 24–36 months | 28–40 months | 28–40 months | 6–10 weeks | 72–96 months |
These are indicative ranges for a custom new build at a top European yard. Semi-custom or series-production vessels can be significantly faster. Yard workload, specification complexity, and owner decision speed all affect actual timelines.
Pre-contract phase
Before a contract is signed, the owner and yard go through a preliminary design and feasibility phase — typically 3–6 months. This involves the exterior designer producing concept drawings, the yard's naval architects confirming feasibility, and both parties agreeing on the specification framework that will form the basis of the build contract. The pre-contract phase is not typically included in the build timeline above but should be factored into overall planning.
Design development
Once the contract is signed, the full design development phase begins. This is distinct from the concept design done pre-contract — it involves developing every system, every compartment, every piece of equipment to the level of detail required to build. For a 70-metre vessel, the design development phase generates thousands of drawings and specifications. The design freeze — when the specification is locked — is typically reached 12–18 months into the design phase for a vessel of this size.
Construction phase
The construction phase begins at the design freeze and runs to launch. For most vessels, hull construction and the early stages of outfitting run in parallel — machinery spaces are fitted out while the superstructure is still being built above them. The keel laying ceremony is typically held 3–6 months into construction; launch occurs when the hull is structurally complete and watertight, ready to float.
At Lürssen and similar yards, construction happens in covered building halls — protecting the vessel from weather and allowing year-round work. This is a structural advantage for northern European yards over open-air construction common in some Mediterranean and Turkish yards.
Outfitting phase
The outfitting phase — from launch to the start of sea trials — is where most schedule slippage occurs. The coordination of hundreds of subcontractors, the interdependencies between systems, and the inevitable discovery of design issues during installation all create pressure on the schedule. The most effective mitigation is an experienced project manager representing the owner who can escalate issues and enforce schedules.
Interior fit-out runs in parallel with outfitting and is typically the most time-sensitive element in the final months before sea trials — joinery is often the last major item to complete, and delays here directly push the sea trial date.
Sea trials and delivery
Sea trials are typically scheduled 4–8 weeks before the intended delivery date, allowing time for snag rectification following the trial programme. The sea trial schedule is agreed with the classification society, whose surveyors attend key tests. Most yards conduct a preliminary harbour trial before the open-sea programme to identify any obvious issues.
Common causes of delay
The most frequent causes of build schedule overrun:
- Late owner decisions: Every day a decision is delayed at a critical path stage delays the delivery date. Design choices, equipment selection, and material approvals all have lead times.
- Specification changes after design freeze: Changes after the freeze are expensive and time-consuming. A major change can push delivery by months.
- Specialist equipment supply delays: Bespoke items — custom stabiliser systems, specialist generators, custom joinery materials — have long lead times and are not always delivered on schedule.
- Classification survey scheduling: Class surveyors must attend specific milestones; their availability can affect the schedule, particularly at busy periods.
- Weather: Open-water sea trials require suitable conditions. Extended periods of bad weather in northern Europe can delay the trial programme.
A 10–15% schedule overrun should be treated as normal and planned for. Owners who build a buffer into their planning — particularly around crew start dates and initial voyages — are better positioned to manage overruns without disruption. For more on the build process itself, see how a superyacht is built.