notches and galv box lids

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Is this acceptable??

I'm rewiring just the sockets in a house with solid floors downstairs.

So under the upstairs floorboards there are loads more cables all running through notches. Is it ok for me to run my new cables through these and put galv box lids on?

 
Aint they gotta be 50mm deep now?? and youd have to work out grouping factors if you bunched them together whilst making your cable selection?? hth

 
have a look in the OSG gives a good diagram explaining it all. sorry cant remeber the page number.

 
7.3.1 OSG

A cable passing through a joist or ceiling support shall:

i) be at least 50mm from the top or bottom, as appropriate,

ii) have earthed amouring or an earthed metal sheath,

iii) be enclosed in earthed steel conduit or trunking, or

iv) be provided with mechanical protection sufficent to prevent penetration of the cable by nails, screws and the like. (Note: the requirement to prevent penetration is difficult to meet).

 
they should be 50mm deep, but if notches already there, adding more holes may do more damage to joists, so you could use them. not sure if galv box lids would be big enough (with them being round)

 
A galv box lid isnt the strongest of metal but it would take some hammering to get a nail through?

 
they should be 50mm deep, but if notches already there, adding more holes may do more damage to joists, so you could use them. not sure if galv box lids would be big enough (with them being round)
They did look like they would manage it, I could always use a bit of metal trunking cut and drilled to suit.

 
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