Which should I do first?

~Chameleon~

I have a small brick built lean-to and want to line the walls & roof to use it as a utility room. What's the easiest/cheapest method of doing this please? Can I just use plasterboard and tile straight onto that or would it need complete plastering/skimming?

Also need to run electric and cold water supply through for washing machine and a sink (pretty straightforward direct through internal wall) and drainage out (again very straightforward as there is a drain next to one of the external walls) but which do I need to do first, the electric/plumbing bits or the walls/ceiling?

eco-friendly_2

1 Check it out with building regs first

2 Install plumbing and electrics

3 Plasterboard ceiling

4 Plaster or plasterboard walls ( depends on the walls )

5 Fit base and worktop for sink and W M

6 Tile or paint finish