Consider ball-valves between you darkroom plumbing and the rest of the house. If you spring a leak in the darkroom it will be much easier to fix if you can just shut off the darkroom, and not have to shut off the whole house and drain it. Also, when on vacation, you may sleep better knowing your darkroom water supply is shut off. Especially if you do the plumbing yourself.
Originally Posted by CPorter
Also, if you move and want to take your water panel with you, it will be a lot easier to do if you have the valves there.