I wonder what the consequences of "
not" notifying such a job would be
I also wonder whether I personally would be that concerned under these circumstances,in fact,being both the client and the installer
I would tend to think in the great scheme of life, its not such a pressing issue notifying a job to a council that has historically not been too concerned with delving into what you do in your own home, or the implementation of a failed building regs procedure such as Part P
I would however be concerned that I do the job to a safe standard and ask others with the experience if what I propose is a correct method
Oh,I notice that is exactly what you have done by posting on here
Now,Part p silliness aside,lets see if we can help you with what actually is important
First think about what outcome you want to achieve,the loading that will be expected,the distance the garage is from the supply and the supply type,the type of cable and method of protection you desire,then confirm what you have at present and what you need to do to alter/renew/install
Get the design work sorted before the practical work to be clear on the whole of the job before picking up your tools
Post up all the information you can and you can be helped with the choice and installation that "you"make for this work