Information for Designers

Updated 5/1/18

IRC's Design Trial service is available for designs still on the drawing board, and applications may be sent direct from the designer to the Rating Office (or UNCL for designers in their 'catchment' area). As soon as the boat is launched it is no longer a design trial and must apply for a valid certificate.

IRC and Design trial policy

Design trial fees & forms:

Initial trial (01)  50% of the fee quoted on the new application form  (ex VAT.   VAT applies to UK design offices)

Please request an application form from the Rating Office.

When sending the application please attach the following design drawings:

- Profile including appendages
- Sail plan
- Accommodation GA
Subsequent trials (02-06)  Fee as calculated on the trial form (ex VAT.   VAT applies to UK design offices)
Please request the current Trial form from the Rating Office (only give data that differs from trial 01) and attach drawings if any changes are being made to hull, appendages, rig configuration or interior.
If you have any questions about running Design Trials please contact us: 

Short-handed certificate

"I do some short-handed racing (1 or 2 people), and use a different configuration than when racing fully crewed"

You can hold a second, 'short-handed' certificate. IRC Rule 8.2 gives details of which measurements or confifgurarion may differ from the primary certificate, and when the short-handed certificate may be used.

Please note that the crew number itself has no effect on the rating, so you do not need a separate short-handed certificate if the boat will be in the same configuration as when fully crewed.

You must hold a current, valid IRC certificate before applying for a short-handed certificate.

Please save and complete the relevant form below and then apply through MyIRC.

Short-handed certificate application first application

Short-handed revalidation where short-handed certificate held in 2012, 2013 or 2014



"I have a current IRC certificate and want to see what difference some changes might make to my rating"

You need to run one or more trial certificates. 

Running a trial certificate allows you to see what the rating effect would be if you made proposed changes to the yacht, rig or sails. Any number of changes can be made on each trial certificate. Trial certificates are NOT valid for racing and will not change your current valid certificate; if you decide to implement the change you will need to apply for an amended certificate.

The number of trials you can run each year is limited, and we reserve the right to refuse to run trial certificates if we feel that an attempt is being made to take advantage of the Rule. Please see the trial certificate policy below.

Please make sure you give full details of the proposed changes to avoid any misunderstandings, and send any drawings as requested on the trial form.

Trial certificate policy

Download Trial certificate form (2015) Please save the Excel form to your computer before completing it:



"I have just bought a boat that has a current (2015) IRC certificate, and need to transfer it into my name"

You will need to apply for a new certificate, as change of ownership invalidates the certificate. If you are not sure whether the certificate is current you can check on the online listings.  You should make sure you have a copy of the last certificate as you need to declare whether there have been any changes and whether details on the certificate are correct. We can help with this if you do not get a copy with the boat. 

We are currently offering re-registration at a special rate of just £1.50 per metre (ex VAT).

Download Re-registration form (2015) (XLS)


"I have a current IRC certificate but have made some changes"

If you change anything on the boat, or buy new sails etc. that may affect your IRC Rating, you will need to apply for an amended certificate. You can make any number of changes for the price of one amendment.

If you are not sure whether a change you are making will require an amended certificate, please contact the Rating Office. In some cases we may just ask you to write us a note about a change which we can keep in the file for our information.

Common changes which require an amended certificate are :

  • new sails, either larger or smaller
  • addition or removal of sails
  • new or changed rig details
  • added or removed internal ballast
  • keel change
  • hull change, eg. fairing of IOR crease
  • weighing/measurement

If your certificate is Endorsed and you wish to keep the Endorsed status, we will require official verification of the new measurements. For instance, if you are having new sails the new data will need to come from an IHC loft or official measurer on a sail input form (which they should have, or can get from us). In other cases we will need a measurer to check new measurements.

We reserve the right to refuse to amend a certificate if we believe that the amendment is intended to take advantage of specific race conditions (eg. rating with a No.3 only, two days before a weekend when it is forecast to be windy!)

Please download and save the Excel form to your computer before completing it:

Download amendment form (2015)

Seahorse Rating Ltd, Seahorse Building, Bath Road, Lymington, Hampshire, SO41 3SE.
Registered in England, Company Registration Number 2041269

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