Installing PIR security lights on a timber-faced house - electrical cabling question

[Shug]

Hi,

I live in a timber-framed and timber-FACED house. (Built around 1960 from Swedish Timber.) At the bottom of the house, all around, there are about some layers of brick, which appears to be at cellar level.

I want to fit some PIR security lights on the outside of the house, but I'm not sure how the electrical cables from the light unit should be run to the house.

We've been told that you can't just drill through the house (not that we would anyway) because it'll breach the damp-proof membrane in the walls.

The only path I can see is to come down the (timber) face of the house and gain access through the bricks, under the floorboards and then back up through the floorboards to the consumer unit.

Can anyone advise for/against this?

Who'd be the best type of person to install PIRs - electrician? Would your average electrician be aware of not just drilling through buildings and breaching the membrane?

Thanks in advance for any help!

Shug

[Owain]

Sounds reasonable. However you have to ensure that the cable is of a type suitable for use in this location. A particular concern might be the application of preservatives or other wood treatments as some types of cable could be damaged by this. You might wish to consider Hi-Tuff in PVC conduit, which takes paint very well so you can paint it to match the house.

They would if you told them, in writing, when asking for their quotation. You would need to know how deep they can drill for fixings etc.

Owain

[David Hansen]

On Tue, 13 Nov 2007 05:12:39 -0800 someone who may be Shug wrote this:-

What about going up?

Of course doors and windows breach the membrane, with larger holes than for a cable. Provided that the hole for the cable is made properly what would be the difference?

[Shug]

David, your point in particular was interesting. Someone else had suggested similar: why can't you just go straight through the outer timber, inner membrane, right through to the inner plasterboard.

However, someone else had said not to breach the membrane.

But you've made a fine point - the double glazing windows already breach the membrane, and it's ok presumably because they're sufficiently sealed.

I'm now thinking that this *may* be an easier solution that going up through the attic, or down through the cellar.

So, in a nutshell, if they install these lights, and adequately seal the point of entry through the outer timber (even though the membrane gets pierced) this looks like a very possible solution.

Then they only issue is routing the cables internally.

Thanks again for your input.

Shug