Accurate measurement is the foundation of an accurate IRC rating. The IRC Rating Authority has published a major rewrite of the IRC Measurement Manual, giving measurers, Rule Authorities and boat owners clearer practical guidance for measuring the huge variety of boats that are rated within IRC.
For owners and competitors, the benefit is simple: measurements that are accurate, repeatable and established consistently help ensure that IRC ratings are based on reliable information, wherever in the world a boat is measured. This strengthens confidence in individual certificates and in the fairness of IRC racing as a whole.
The extensively revised Manual goes well beyond a routine annual update. Expanded guidance on weighing covers measurement condition, load-cell selection and calibration, alternative methods and the importance of single-point lifting. It also emphasises the need to accurately recording the boat’s condition so that results can be understood and repeated.
Guidance has also been updated for hulls, appendages, rigs and sails. New and expanded sections address features including interceptors, lifting appendages and twin rudders, as well as unusual rig arrangements, sail corner points and leech hollows. Quick-reference appendices provide practical support for more specialist measurements such as bulb weight and list angle.
The Manual also incorporates IRC Rule changes taking effect in 2027, helping the international IRC community prepare for the new certificate year.
Owners planning measurement, modifications or an Endorsed certificate are encouraged to consult the revised Manual before work begins and contact their local IRC Rule Authority where advice or measurement is required.
