No idea what the fines for not being good little boys and girls and telling the council will be, but how exactly do they propose to enforce it against the DIY homeowner?

Now if somebody decides to built a 400 sq. ft. extension without the council's permission, it's noticeable, and if somebody reports it within the required time period (is it 3 years?) then legal problems could follow.

But wiring is different. It doesn't show on the outside of the house (well, most of it doesn't!). There are no official records of what electrical systems are installed in homes. So at least in the early stages, even if some council pen-pusher did try to query something, the homeowner just says "Oh that as done back in 2004." How does the council prove otherwise, unless every new device is going to be date coded?

But proof is really beside the point. How is the council going to know that somebody has added a socket, or changed a light switch in his own house to even query whether some "illegal" work has been carried out in the first place?

As far as I can see, for the average DIYer the new regulations will be totally unenforceable.