Who assigns a yacht’s CE design category — and where 65–78 ft cruising cats sit

The four EC / RCD design categories

These categories (often still called “EC categories”) come from Directive 2013/53/EU (the Recreational Craft Directive, or RCD). They describe the intended wind and sea conditions the boat is designed and built to meet — not a weather forecast or a legal limit on where you may sail.

Who decides the category, and how?

The manufacturer (or the person placing the boat on the EU market) chooses the design category and is legally responsible for it. A designer or yard cannot simply “claim” Ocean if the boat does not meet the essential requirements for that category.

How compliance is shown

• The boat must satisfy the RCD’s essential safety requirements for the chosen category: structure, stability and buoyancy, openings, steering, engines, gas, electrical systems, fire protection, and so on.
• In practice this is done against harmonised ISO standards, principally:
  • ISO 12217 (stability and buoyancy assessment) — this is usually the binding constraint on category;
  • ISO 12215 (hull construction / scantlings);
  • plus ISO 8666 (principal data), ISO 14946 (maximum load), ISO 9093 (through-hulls), ISO 10240 (owner’s manual), and others.
• Stability calculations (righting moment, downflooding, inversion recovery or residual buoyancy for multihulls, wind heeling, etc.) are run for the declared maximum load and crew. The highest category the numbers support is the highest category that may be declared.
• The manufacturer draws up a Declaration of Conformity and affixes the CE plate (which shows the design category, builder, max load, max persons, etc.).

Role of a notified body

For most boats in categories A and B (and for many larger category C boats), a notified body (an independent EU-designated inspection organisation) must be involved — typically EU type-examination of the design plus production surveillance. The yard cannot self-certify Ocean or Offshore on a 20 m catamaran. Category D (and some small C boats) can use lighter modules.

Boats with hull length 24 m and over fall outside the RCD. They are treated under large-yacht / passenger / commercial codes (MCA LY3/REG, Passenger Yacht Code, class society rules, etc.). Many 65–78 ft production cats are deliberately kept under 24 m hull length so they remain in the RCD.

Typical 65–78 ft cruising catamarans — estimated mix

This size band (about 19.8–23.8 m) covers production and semi-custom ocean cruising cats: Lagoon 65 / Sixty 5 / Seventy 7, Fountaine Pajot Alegria 67, Privilege, some Leopard / Robertson & Caine flagships, Excess larger models, Bali / Catana larger models, Sunreef 60–70 range kept under 24 m, and similar. These boats are marketed for bluewater and transocean use.

There is no public register of every CE plate, so the split is an informed estimate, not a census:

• At this length and displacement, ISO 12217 stability and downflooding numbers almost always support Category A if the boat is designed as a serious cruiser (adequate bridgedeck clearance, reserve buoyancy, intact and damaged stability, limited downflooding points).
• A handful of models or one-off builds may be declared B if the yard did not complete (or did not want to pay for) full A assessment, if maximum load / flybridge / extra tanks pushed the stability case over the A limit, or if the boat is a coastal-oriented semi-custom with large openings. That is uncommon among the popular brands.
• Categories C and D are for much smaller or purely sheltered craft. A 65–78 ft cruising cat in C or D would be commercially and technically anomalous.

Charter versions of the same hulls are still typically Category A; charter operation is a commercial overlay (MCA, flag, local coding), not a lower RCD category.

Other classification and coding systems

• ISO 12217 itself — the calculation method behind RCD categories; some non-EU builders quote ISO category even without CE marking.
• Class societies (Bureau Veritas, RINA, Lloyd’s Register, DNV) — hull and systems class, more common on semi-custom and 24 m+ yachts; can be combined with CE for under-24 m boats.
• MCA / REG Yacht Codes, Passenger Yacht Code — UK and related flags; commercial or large-yacht operation (categories of operation 0–6, or PYC). Independent of CE design category.
• United States — no RCD equivalent. NMMA certification to ABYC standards is voluntary for production boats; USCG rules apply if the vessel is documented for commercial use (passenger counts, subchapter T/K, etc.).
• Australia / New Zealand, Canada, etc. — national recreational standards; CE Cat A is widely accepted as evidence of ocean capability.
• Racing / IRC / CSA — rating rules, not seaworthiness categories.

CE design category remains the single most common “seaworthiness label” on production cats sold worldwide, because so many yards build for the European market.

What most designers of these catamarans actually design for

Category A (Ocean), using ISO 12217-2 (multihulls) and ISO 12215 scantlings as the structural and stability baseline. Marketing, owner expectations, and insurance for 65–78 ft cruising cats all assume transocean capability, so yards design to A unless there is a specific reason not to.

Typical extra design targets beyond the RCD minimum:

• Bridgedeck clearance and slam loads for trade-wind ocean work;
• Positive residual buoyancy / inversion considerations for multihulls;
• CE maximum persons and load that still leave a usable payload (water, fuel, toys);
• Optional class or MCA coding if the client wants charter or commercial use;
• Keeping hull length under 24 m to stay inside the RCD rather than large-yacht codes.

In short: the manufacturer chooses the category; a notified body checks A/B boats; ISO stability and structure decide what can honestly be claimed; and virtually every popular 65–78 ft cruising catamaran is designed, assessed and plated as Category A.