Might be a silly question this but is there a standard convention
concerning the routing of wires in a house? I would like info
specifically on light switches; so if I am looking at a light switch
in my lounge, would the wires go straight up, straight down or what?
Are the upstairs switches different? My house has a concrete floor so
the wiring cannot go under the floorboards - don't know if that makes
a difference or not.

The reason I ask is that I need to do some drilling and although I
will use a cable detector first, I would like to avoid any obvious
pitfalls.

Many thanx,

Andy.