I am buying a house where the domestic fuse box is in a detached garage 4 metres away. It was installed when the house was built in 1970. Is this now legal or will I need to get the fusebox moved into the house?
Nothing has changed to make something fitted which was legal at time of fitting illegal now.
There have been a number of changes in the regulations and when you get your electrical condition report which is required with occupant change (although often missed) you will likely get many Code C2 and C3 items where changes are recommended.
Only changed in January this year was a periodic inspection report and I am uncertain of new codes but unless you get a code C1 would not be too worried.
Today houses all have RCD protection and the main problem is to add anything has to comply with new regulations so until you get the consumer unit up-dated it will be hard to get anything else done. Not impossible but hard and often more expensive then one would expect because RCD FCU and like have to be used.