Routing cable through external wall - questions?

Arfa__

Work on installing our conservatory starts next week, but before they start I want to lay down some audio cable to pipe music from our lounge in there. Just going to be a run of screened audio cable, not too long <10m, terminating at a wall socket in the conservatory. Just got a quick query about the route and going through the external wall.

My initial thoughts are under down stairs floorboards in hall/bathroom and straight out. With this route, I'd be going through the external wall quite low down, below boards in side (near air bricks I guess), then up on other side. Any issues here, with damp course etc? Conservatory floor will be above point I go through wall once finished. Can I just pass cable through holes in air brick - save drilling more holes?

My other choice is up, then run across between ceiling and upstairs floor boards, out external wall high up, then run down outside/inside conservatory. Longer route and longer trench in outside wall to knock out to bury cable.

Any issues with bashing a trench in render on outside to bury cable? It will be inside conservatory once built and their plastering this wall it smooth afterwards anyway. Of course I'll be covering it with steel protection in case of Muppets with picture hooks!

molerat

Go through airbrick if it is the easiest route, a couple of wires will not cause any problems. I would check with the plasterer what he intends to do with the render first, he may want to knock the top coat off. I removed a whole brick above the dpc for mine but that was for 2 x 22mm pipes and electric cables.