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Ship Retrofit Design

Ship Retrofit Design

What is ship retrofit degisn

Engineering modifications to existing vessels — new equipment, updated regulations, or operational repurposing.

Ship retrofit design covers the engineering required to modify an existing vessel. Unlike newbuild design, retrofit engineering must work within the constraints of an existing hull, structure, piping network, and electrical system — every modification needs to fit into what is already there without compromising structural integrity, stability, or class status.

Who needs retrofit design

  • Shipowners upgrading their fleet to comply with environmental regulations — ballast water treatment, SOx scrubbers, or EEXI improvements
  • Offshore vessel operators converting PSVs or anchor handlers for new operational roles
  • Ferry and passenger vessel owners undertaking life-extension or capacity-upgrade programmes
  • Shipyards requiring detailed design packages to execute retrofit scopes efficiently

Scope of work

  • Structural design — reinforcement, insert plates, equipment foundations, deck strengthening
  • Piping and machinery arrangement — new equipment integration into existing systems
  • Electrical design — cable routing, load balance checks, switchboard modifications
  • Outfitting and accommodation — crew capacity upgrades, new cabins, public spaces
  • Stability and longitudinal strength verification — intact and damage conditions

When original drawings are unavailable or contradict the actual ship, 3D laser scanning provides the as-built baseline. The design package covers concept through to class submission documentation, including classification society approval and yard-ready fabrication drawings.

Project experience

BWTS retrofit — 20+ vessels — structural integration, piping design, and electrical tie-in for ballast water treatment systems across multiple vessel types and shipyards.

Ferry life-extension retrofit — structural reinforcement, new accommodation block, and updated fire safety arrangements for extended service life.

Cargo vessel conversion — repurposing a general cargo vessel for specialised transport, including hold modifications and new equipment integration.

Frequently asked questions

Do I need 3D laser scanning for a retrofit?

It is strongly recommended when the vessel’s as-built condition differs from the original drawings, or when drawings are incomplete. For complex retrofits in congested machinery spaces, 3D scanning significantly reduces fit-up risk during installation.

Can retrofit design be done while the vessel is in service?

Yes. The design phase is normally completed before the vessel arrives at the yard. The engineering team works from existing drawings, 3D scan data, or onboard surveys during port calls — so yard time is used only for execution, not design development.

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