I am planning an all-year-round shed/den/garden office which will need the full range of services. This may sound a bit extravagant but we need to use it as a temporary bathroom while some major work is done on the house. It seemed a good opportunity to get the ultimate shed at the end of it!

For the drain, I am going to put an inspection chamber next to the shed and run a straight length of pipe in a suitable trench to the nearest manhole (in my garden). My questions are:

1. Can I (regulations or otherwise) run a water pipe and an electrical cable in the same trench next to the drainpipe?
2. Is it better to use sheathed cable directly in the ground or ordinary cable in a conduit? If the latter, what's the best thing to use (for the conduit)?
3. Is it better to bring the drain and water up through the shed floor or in through the wall? Neatness and frost protection suggests through the floor would be best but they wouldn't be so accessible.
4. I know electrical work is tightly regulated. Do the regs just cover getting a qualified electrician to connect everything up or wiil they need to be involved in sinking the cable?
5. Do I need a vent stack for the drain? As the top could only be at shed roof height, might this cause problems with smells in the garden?

I suppose my preference would be for channel-tunnel-style twin 100mm pipes, one for the drain and one for everything else. That would make it very easy to run further cables etc. in future if required. Is that a good idea?

Hints, tips and wise words of wisdom on any or all of the above most gratefully received. Thanks in advance.

Julian

Thanks very much for those comments and the link to your articles. Very helpful. I'm coming to the view that I will have the drain pipe at the bottom of the trench in the middle. On one side and about level with the top of the drain, I'll have the armoured mains cable. And on the other side level with the top of the drain, I'll have the water pipe and a conduit for network etc. The trench will be 45-50cm wide so that should give good separation between mains and network cables.

Julian