The answer to this question is it depends
if you have an NHBC warranty then there is a requirement to have a 5 lever locking mechanism or similar install installed in the door between the house and the garage
If however for example you had a for example you had a Premier warranty or similar other warranty they do they do not have the same requirement And there’s nothing in their technical standards to require them to install a locking mechanism
Inevitably your insurance company will ask I will ask you about the locks that you have in your house when you apply your house when you apply for insurance and they too will wish require you to require you to have a minimum of 5 Or multiply locking system to the garage door
All grand floor doors and windows should have some form of locking mechanism fitted.