I watched my neighbor's electrical "contractor", that arrived in an unmarked bakkie and do the following earlier this week:

I gather that they lay a cable to a pump at his big JoJo drum.

1. They drilled a hole from the inside though to the outside right by the DB board in the kitchen.
2. .chased a channel vertically till it reached about 2 foot off the ground. (all outside)
3. .then chased a channel about 5m long along the wall to the back of the house. (all outside)
4. I watched them install a white cable (maybe 3 times the thickness of a 3 core 20amp cable into the channel.
5. They then proceeded to slap cement over the channel and that was that.
6. I can't see where the cable ends (hopefully in a box on the wall) I will try to check (yes I am nosy)

Is this legal?
What happens it next next home owner drills a hole in the outside wall and gets electrocuted?

This sort o thing really scares me because I am a handyman type so I would definitely run the risk of drilling into such an installation.