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Which is best, long ring final with 2 spurs or short ring final with more spurs?

Former Community Member
Former Community Member
Good afternoon, hope you are all well. I have been re-evaluating the number and position of sockets in my bungalow, and considering having a few more added for convenience. Currently I seem to have a relatively short ring with 2 long spurs. If I measure the new route for cables incorporating the existing spurs and new sockets, I anticipate a total cable run of about 100m. From what I gather on this forum this is the limit for a ring final per 100m square of floor. Question is, is this a good idea, or should the ring final be made to run a shorter route and add more spurs, not exceeding the number of sockets on the ring, in order to keep volt drop to within acceptable limits. Not being an electrician I have used online cable size calculators to see if my idea is anywhere close to being ok and they come back with a huge 25mm squared cable. I am clearly out of my depth here hence the question. As always, many thanks in advance. Kind regards, Simon   
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    Are you adding significant new load, or just spreading about the loads you already have - if the latter there is no real need for an additional circuit. If possible I try and add sockets to a ring in a way that they are mid ring, rather than spur as this makes it easier to avoid joins and  jamming 3 cables in a box. 

    2.5mm is the "normal" ring cable,  unless very long  runs or well insulated and badly cooled routes, and it is for this configuration that the 100m round ring length rule of thumb, such as it is applies.

    More importantly, is the existing ring OK - for example is it RCD protected, are there any signs of trouble like nuisance tripping.
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  • 0
    Are you adding significant new load, or just spreading about the loads you already have - if the latter there is no real need for an additional circuit. If possible I try and add sockets to a ring in a way that they are mid ring, rather than spur as this makes it easier to avoid joins and  jamming 3 cables in a box. 

    2.5mm is the "normal" ring cable,  unless very long  runs or well insulated and badly cooled routes, and it is for this configuration that the 100m round ring length rule of thumb, such as it is applies.

    More importantly, is the existing ring OK - for example is it RCD protected, are there any signs of trouble like nuisance tripping.
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