Hi, I’ve been asked to install a FD30 fire blank in a HMO with the door being 680mm wide. Is there a minimum the door should be? I’m reluctant to carry out the works until I have all the information provided to me including drawings.

The appropriate information would be found in the Building Regulations, where they apply, Approved Document M https://www.gov.uk/government/publications/access-to-and-use-of-buildings-approved-document-m