mapj1:
No, I think the intention is always that the spurs are wired in the same stuff as the ring, namely 2.5mm. IF you had 4mm radials the 2 socket limit would make no sense.
In any case the rating of 2.5mmsq is 27A for surface wired or in plaster - which would have been the options when it was being dreamt up. Dont forget that part L and all this thermal stuff ony go t going after the 1984 revisions to the building regs - because until you have central heating the indoor and outdoor temps in all rooms without a fireplace are not so different.
mapj1:
No, I think the intention is always that the spurs are wired in the same stuff as the ring, namely 2.5mm. IF you had 4mm radials the 2 socket limit would make no sense.
In any case the rating of 2.5mmsq is 27A for surface wired or in plaster - which would have been the options when it was being dreamt up. Dont forget that part L and all this thermal stuff ony go t going after the 1984 revisions to the building regs - because until you have central heating the indoor and outdoor temps in all rooms without a fireplace are not so different.
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