Cable conduit under screed flooring?

[HomerSimpson]

I am project managing my own house extension and need to know when to arrange for the screed floor to be laid. I know that the plumbing will run under the screed but do the electrians bury the ground floor ring main in a conduit before the screed is laid too? Or is it chased in at skirting level?

 

[plugwash]

usually with a concrete floor downstairs cables for sockets are dropped down from the ceiling void

 

[breezer]

it really depends on what the architect says, and can it be done


as for
usually with a concrete floor downstairs cables for sockets are dropped down from the ceiling void what if its a flat roof?

sorry i disagree with that one

 

[andemz]

You could still possibly have a void even if it is a flat roof. I had on the back of my house a very large summer house which consisted as single storey flat roof. The wires all came from a small void in the ceiling. It is now knocked down and i am building a double story extension with conservatory.

i don't really like the idea of burying cables under screed/concrete doesn't rest right with me.

Having said that, there was a tv programme called grand designs. they laid miles of cable in the floor in this trench, the trench then had a, what seemed steel lid that ran all the way down the trench and then they just lushisly poured the concrete or should i say pumped the concrete all over it. I guess there would have been inspection places etc but it looked pretty much buried to me.... Is this allowed?

 

[securespark]

I would say so, yes. As long as provision is made for drawing in replacement cables, I see no problem.

After all, conduit sunk in screed is just that. You can access one end and the other and draw in cables using a fishtape or the existing cables. No problem.

 

[breezer]

so long as there are access points at any major turn/junction and the space factor is not exceeded it is pefercly acceptable

 

[plugwash]

i don't belive there are any permitted routes for cables in conduit just under a floor surface

so the conduit should definately be metal and earthed

 

[breezer]

it should be galavanised conduit, and by design it is earthed.

 

[Lectrician]

Cables may be run under a floor as long as they 'are unlikely to be damaged by the intended use of the floor'

PVC conduit is used very often, maximum of 2 90deg bends though remember

I have only run cables under floors in commercial properties, and always opt for galv conduit.

A flat roof will still be able to conceil cables during the build.

 

[ban-all-sheds]

A flat roof will still be able to conceil cables during the build.

Yup - just bury them in the cealing....

 

[HomerSimpson]

Its a 2 storey extension not flat roof.
Thanks for the advice everyone.