Electrical wiring under screed

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For crossing from one side of the house to the other I am considering running a bunch of cables under the floor insulation/screed. Is that allowed?
 
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Yes, normally fine. I would always put the wiring in a pvc conduit though, to be on the safe side.
 
Can I then have wires up from the floor into wall sockets and higher up the wall into the ceiling lights?
 
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Might need metal conduit for mechanical protection And if so the conduit would need earthing.

I would run the conduit to a back box each end at normal accessory height just in case I ever need to replace the cable.
 
So, in every room, there are wires on the concrete slab (inside some conduit maybe) shooting up into the wall, for the power sockets, and continuing upwards and then into the ceiling for lights.

Or I can have just on wire into every room, into the first "box" into the wall, and from there, if possible, feed the rest of the room.

Or a combination?

In the end it will look more like a star system, is that even allowed in the UK? I thought all wires have to form rings?

Sorry for asking noob questions.
 
So, in every room, there are wires on the concrete slab (inside some conduit maybe) shooting up into the wall, for the power sockets, and continuing upwards and then into the ceiling for lights.

Or I can have just on wire into every room, into the first "box" into the wall, and from there, if possible, feed the rest of the room.

Or a combination?

In the end it will look more like a star system, is that even allowed in the UK? I thought all wires have to form rings?

Sorry for asking noob questions.
You need separate wiring for lighting circuits and power circuits.

There is no requirement for rings, where ever did you get that idea?
 
OK so we have two cables running into each room, from the floor, upwards into one or more walls. One wire is for sockets and the other is for lights.

Going upstairs I am thinking of having a very thick cable up the staircase space, then maybe an independent fuse box just for the upstairs on the landing?
 
OK so we have two cables running into each room,
It's possible to have separate power and lighting circuits for each room, but highly unlikely it's required or even desirable.
Doing so will use vastly more cable than more usual methods, and result in a consumer unit that's 10x larger than required.

an independent fuse box just for the upstairs on the landing?
Totally pointless.

I thought all wires have to form rings?
That has never been a requirement.

wires up from the floor into wall sockets and higher up the wall into the ceiling lights?
Theoretically, but what about switches for these lights?
It's more usual to install cables for lighting in the ceiling where they are required, rather than as far away as possible in the floor.


I suggest paying someone to design the installation properly, as from the information given so far, you are about to make a large number of very expensive mistakes - and that's before all of the other considerations such as what loads are to be used, where and how cables are allowed to be installed, the size of those cables and so on.
 
Going upstairs I am thinking of having a very thick cable up the staircase space, then maybe an independent fuse box just for the upstairs on the landing?
Fuse boxes are last century. Use a consumer unit.
 

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