Under suspended floor routing of cables.

[nasjjjmi]

Hi, I'm trying to plan ahead for the future. Before I lay a nice new floor in the Lounge I'm thing about requirements for running new electrics to the upper floors of my house, either for a future rewire or for a loft extension. What I would like to do is lay an empty conduit under the floor, attached to the joists from the box, up the wall in box work for heating pipes and then emerging into the airing cupboard. If I've calculated right I would need space for 1 or 2 ring mains, 2 or 3 lighting circuits and 1 or 2 Showers. Obviously this is a lot of conduit if I have to lay a unique one per cable / pair. I'm interested to know if the regs allow you to use bigger dimension piping (ie waste or soil pipe) or if there is a large bore electrical version available. Does anyone know.

Thanks

 

[Taylortwocities]

Of course you can use a bigger conduit/duct and run several cables in there.
Most factories, etc are wired in that way, using cable trunking.

You will have to take account of grouping factor when doing cable size calculations and follow the guidance on the amount of free space you must use.

And do not run other cables (like TV/telephone) in the same duct as the power cables.

PS I doubt that you will have enough power supplied to your house for more than one power shower.

 

[Steve]

PS I doubt that you will have enough power supplied to your house for more than one power shower.

*electric shower.

a power shower only consumes a hundred watts or so. I have one. It is very good. Can stay in it as long as I want and not worry about the electric bill (until the cylinder runs cold). Aaaaaanyway!

 

[ban-all-sheds]

I'm interested to know if the regs allow you to use bigger dimension piping (ie waste or soil pipe)

Don't use either.

or if there is a large bore electrical version available. Does anyone know.

http://www.tlc-direct.co.uk/Main_Index/Trunking_Galv_Index/index.html

Other sizes and suppliers are available.

 

[electronicsuk]

What type of flooring are you planning on fitting? If it's just carpet, it's barely worth worrying about, as it'll easily come up and go back down again without any damage.

If solid floor, it would be wise to try and incorporate an access hatch to allow access to below the subfloor. Not only will that allow you to run in more cables in the future, it will also allow access should you have problems in the future with other services (i.e. heating pipes) that run down there.