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
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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.