Sockets/cables near steel support beam

[JoeJoe]

Kitchen was extended a few years ago, and steel beams were used to support it (a rectangle of I-beams screwed together spanning along each wall, under the floorboards and in the ceiling (see top diagram here

The vertical beams were boxed in using plasterboard.

I am looking to hang a TV on the wall near one of the two vertical beams, and am hoping to:

1) use the space within the beam to run the cables from below the floor to the where the TV will be; and 2) fix the power/Ethernet/Coax sockets to the plasterboard boxing the beam. I would like to use flush fittings with drywall backboxes (see bottom diagram in link above).

I also checked that there is space for the cables to run along the beam and that there is enough room for 35mm backboxes.

Simple question is: is this allowed?

BTW: I do know that the electrician working on the extension used the opposite side of the beam in question to run electrical cables.

[Tim Watts]

Don't see why not...

[newshound]

+1, subject to the usual rules about segregation / separation of power and data.

[Tricky Dicky]

If you are worried then perhaps if the metalwork was earth bonded then that should make it safer. I am not sure if that has to be done anyway. We had some workbenches at my last place of work which multipoint flexible leads a ttached and because of the metal under frames these all had to be earth bon ded.

Richard

[Bill Wright]

Normal practice in, for instance, new hospitals and prisons.

Bill

[spuorgelgoog]

I don't think there are any electrical issues. The main concern is maintaining fire protection to the structural steelwork. You're not in a tower block I assume.

Owain

[JoeJoe]

No, just a standard 2 floor house.

I will be making to holes in the plasterboard boxing the steel beam for the backboxes though.

[spuorgelgoog]

You can put some intumescent stuff in or behind the back boxes if you're worried.

Owain

[JoeJoe]

Thanks, I am not worried at all... Just wanted to check that I wasn't doing anything that was not allowed.

[Tim Watts]

I think the point raised about ELV (signals) and LV (mains) in close proximity is a good one if we treat the void as "containment".

It is very easily solved though - run some self adhesive trunking or flexi conduit up to contain either the mains or the signal cabling. That will satisfy the IET regs.