How long to keep documents
There aren't any specific rules about how long to store governing board documents for, unless they contain personal data (more information on this below).
The Information and Records Management Society (IRMS) recommends retention periods on pages 66 to 71 of its toolkit for schools. The periods vary for different types of documents.
This toolkit isn't exhaustive, and there may be other governing board documents you want or need to store. It's up to you to decide how long to retain these for.
If your documents contain personal data
It's a legal requirement under the UK General Data Protection Regulation (GDPR) to store personal data only for as long as is necessary for the reasons it was collected.
You'll need to work with your school or trust to determine what this means for the documents you hold.
There's no specific requirement to hold documents