DIY Doctor UK DIY Forums

I have just purchsed a newish house with space for an loft conversion. In the original build the main consumer unit has a 40 amp MCB marked sockets. A single line out to the loft is in place (but not connected!) and the cable is capable of carrying at least 40A.

I reckon that the builder planned to install a secondary consumer unit in the loft and run a ring main and lighting circuit out of this unit with the loft from protected by the 40A MCB on the main unit. Is the acceptable under building regs?

Hi, seems perfectly ok to me, you could buy a so called 'garage unit' which comes complete with RCD main sw. plus 1X6A & 1X16A for socket radial, you could change 16A for 20A and wire radial in 2.5mm2, no limit to number of outlets if loft less than 50 m2, then again if you need more power fit 32A for ring or 4.0mm2 radial which will cover up to 75m2,
regards SPARX
N.B. as new circuits means part p rules apply see forum 'projects'

Thanks for advice - much appreciated - since I won't have to open the wall to do a new cable run - it is new work but at least now I know what to ask for!