The following IRC Rule changes were approved by Congress in October 2017:

• In Rule 21.5 the ‘default’ values for mainsail widths have been deleted as this was inconsistent with the Rule on headsails.
• The Dayboat Definition and Rule 24 have been deleted, as IRC cannot and should not judge OSR compliance.
• The final sentence of Rule 8.2.1 has been corrected to reflect the intention of the Rule on short-handed certificates.
Rule 13.2 has been changed in accordance with IRC Notice 2017-01, relating to sail measurement batten length.
Rule 17.1 now clarifies that cushions are only relevant to measurement condition if carried while racing.
Rules 21.2.1 (Rig Factor) and 22.2.1 (Hull Factor) have been updated to reflect actual practice.
• Definitions have been added for the measurement of lifting foils, to reflect the increased use of these and development of how they are rated.
• Other changes are: deletion of the IRC Headsail Head Point definition as this is now identically defined in ERS; a correction to the Advertising Code reference in Rule 26.1; and confirmation that in Southern Hemisphere countries the new IRC Rule does not come into force until June 2018 (the exception is Rule 13.2 as Notice 2017-01 applied with immediate effect from May 2017).

Full details of Rule Changes for 2018

IRC 2018 Rule text and Definitions

IRC Rule changes 2016 – a summary
• Rule 8.1 now includes a minimum LH of 5.00m to be eligible for an IRC rating (excepting boats previously rated)
• Bulb Weight will now be recorded on a boat’s certificate where applicable, and Bulb Weight has been added to Rule 8.10.1 and the definitions.
• Abbreviations for some sail measurements (LLmax, LL, LP, SF) have been updated but the definitions are unchanged.
• The rule about setting multiple headsails simultaneously has been simplified, and new cutter rig definitions added.
• IRC notice 2014/01 relating to reefing of spinnakers is now included as part of the spinnaker definition.
• The definition of a Dayboat now includes an upper LH limit of 10.00m.
• Rule 21.1.6 is extended to include moving the mast at foot or deck level for Dayboats.
• Rule 9.8 rating review limits are amended in respect of weights.
• A number of detail changes have been made throughout the text to correct typographical errors and inconsistencies in terminology, and the definitions have been re-ordered in categories for clarity.

Download full 2016 rule text & definitions


Extract from IRC Rule text which is copied from the 2017-2020 ERS.   Items in bold are as defined in ISAF Equipment Rules of Sailing (ERS) Part II, Definitions.

17 17         BOAT WEIGHT

17.17.1      Boat Weight is measured in accordance with the following Conditions for Weight and Flotation Measurement:
            The boat shall:
                        be dry.
                        be in compliance with the class rules (ie. IRC Rules)
            Unless otherwise specified in the rules, any of the following shall be included:
                        rig including spinnaker pole(s), whisker poles and/or jockey pole
                        main sheet and mizzen sheet,
                        inboard engine or outboard engine in stowed position,
                        fitted berth cushions on board in their normal positions,
                        all permanent fixtures and fittings and items of accommodation.
            Unless otherwise specified in the rules, any of the following shall be excluded:
                        fuel, water, variable ballast or the content of any other tanks,
                        gas bottles
                        portable safety equipment
                              and all other unfitted or loose equipment.




The following Rule changes come into effect on 1st January 2014 (1st June 2014 for South certification year).

  • Rule 8.2.1 is amended to clarify that short handed boats may be included in the overall results of a race.
  • Rule 9.6 is amended to clarify from what point a rating protest is applicable.
  • Following a change to the RRS, a new IRC definition of Stored Power is added and referenced in Rule 15.
  • Rules 13.1, 22.1 and 22.2 have been re-written to be clearer and more logical without changes in meaning.
  • Rule 21.3.5 is deleted as redundant and potentially misleading in that it is repeated in other rules using different wording.
  • The definition of LP is amended to formally incorporate IRC Notice 01/2013 clarifying measurement of LP for boats that may set more than one headsail simultaneously.

Download PDF version

Download full IRC 2014 Rule text

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John Crawley (CAN IRC)  
Jinno (c/o JPN IRC)
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