Running electric cable in concrete floor

On Sat, 17 Feb 2007 14:45:05 +0000, Broadback mused:

If I were running cables in a concrete floor I would prefer to run them in galv tube, or PVC at the very least. Galv would be safest but either way it's not a major chore to replace the cables if required without it being a major headache as long as the tube is installed with this in mind and also with enough space to get the cables through (e.g. 1x20mm for a ring across a floor round 2 90 degree bends is not going to be great).

Personally I just case them in the concrete..keeps em cool ;-)

Twin and earth cable is unsuitable for embedding directly in concrete. This is clearly stated in the OSG and in GN1.

Well slip a bit of flexi conduit over them if you feel precious.

Ive seen it done plenty of times..the sort that can happen is the insulation fails in 30 years time..and you have to chisel it out again..

Years ago could get prewired flat section PVC trunking for just this purpose. IIRC the cable was single insulated and loosely in its own section of the trunking. It was used for wiring in blocks of flats Never used it myself so not sure how the sections fitted together

Don't know if it is still available

Tony

On Sat, 17 Feb 2007 14:45:05 +0000 someone who may be Broadback wrote this:-

Install conduit in the floor, with easy bends where they bend up to the walls. Put in draw strings (thin nylon rope is best) and draw in singles which are terminated at the first accessory.

Run horizontally in your preferred wiring system between accessories along the walls, so that you minimise the number of conduit runs under the floor.

Beware of Mr Prescott if the house is in England or Wales.

Should be OK if the foundations are substantial enough....

Thanks folk.