connecting up an outside hot water feed?

[epipeinfo]

I already have a cold water feed to an outside tap. This feed tees off the cold water pipe to the kichen sink and appears to comprise of a gate valve followed by what I think is a check valve (possibly double?) and then on to the outside tap itself. I'm looking to do something similar with the hot water but use the same external tap i.e. both hot and cold feeds will eventually be connected together before reaching the outside tap. I'm thinking of replicating the use of a gate and (double) check valve, like the cold water side. I'm also thinking of using two ball valves (one for each feed) so I can quickly switch between either a hot/cold water feed to the outside tap. The order of connection would be tee from kitchen sink pipe, gate valve, (double) check valve, ball valve then finally via a T or Y connector to join both feeds to the outside tap. I'm not intending to feed both hot and cold water at the same time. Can anyone with some plumbing experience tell me if this is a reasonable idea or where I may be able to improve on it (i.e. regs or components). Edit to add that I have a closed hot water system, so my hot water is at (or close to) mains pressure.