Adding a new double socket

[jz5ccn]

I plan to have a socket added to an existing ring or radial circuit. The circuit has around 7 double sockets on it already over an area of approx. 40M2. I would have to take up a lot of floor boards to determine actual routes and lengths of existing cable.
I do have an easy access point to the supply and return cable of an existing socket, just below where I want the new socket.
So my question is whether I can just add the new socket 'in-line' with one of these cables?
That is;break one of the existing cables, add a junction box to divert to new socket then back from new socket to junction box and then continue as before.
Is this possible or will my electrician want to rip up all my floorboards and rewire entirely.
The existing circuit is protected by a 30A fuse at my CU.

Thanks

 

[BigJon]

If its a ring main you have, you can "spur" off any socket, or at the fuse at the board. Yes you can break in to one of the cables, aslong as ring continuity is kept its not a problem. If its a radial you can just tap off any existing socket. your electrician shouldnt need to rewire the circuit - just add to it