MJF1981

Hi! Forgive me if this has already been answered but I would like to know whether the requirements for fire doors between a garage and house are for new-builds-only, or apply to all houses. I've just started renting a 1930s detached house with a garage, which has a door leading to a utility room, which has a door leading to the kitchen. Do any of the doors need to be fire doors? As this is a rented property, it would need to be a 'requirement' rather than just a 'recommendation' in order for the landlord to do it. Please can you advise?