This one may get a little more confusing to explain, especially since I don't know how to sketch a diagram. Here goes:

I have a customer that would like to turn his backyard frost free silcock into warm water. Everything is finished in the basement but the plumber actually teed off under the basement lavatory and put shutoff valves and drains in. The shutoff valves and drains also control the garage faucets (hot and cold). This means the cold shutoff valve under the lav controls the backyard faucet, and the garage cold faucet and must be tied together somewhere in the finished part.

Here is what I propose to do, and you guys tell me if there is any potential problems with it, or if there is a better way:

I am planning to reverse the hot and cold in the garage for starters (done in the cabinet) and make the left faucet (in the garage) the cold so that he will have 1 cold and 2 warm and not 1 hot and 2 warm. Then I am going to use a tempering valve for the (new) warm in the backyard and the RIGHT side in the garage.

Hopefully this is not too confusing. If you get the grasp of what i'm proposing, I think it is pretty straight forward, other than all of the work that needs to be done in a little vanity. Please let me know if what I plan to do is not a good idea.

Thanks!

why not just put a moen hot/cold outside faucet?

How does he have "one cold and two warm" and how will you get "One hot and two warm" faucets. Your description does not tell us WHAT you intend to do or how you will actually do it.

I know, it is very confusing without seeing it or having a picture.

Packy- I am not removing any outside faucet or replacing them. All of the silcocks are going to remain so that I do not have to disturb drywall (per his request)

hj- Picture this: One cold silcock out of the back, and hot and cold in the garage. All three of them are passing through dedicated shutoff valves under the basement lavatory. The two colds tie in together somewhere in the finished ceiling above.

What HE wants is to have warm water in the back of the house somehow, with no damage to drywall. The only way to do that would be to temper the water. If I did this though, it would temper BOTH the backyard silcock and the garage cold since they are tied in together. Upon doing this, it would leave me with two tempered faucets and one hot, and that is the reason I would reverse the piping under the lav so that he would have one cold and two warms.

All of the work is going to be done in the lavatory vanity. It is just such a strange request, and also strange because it is even possible since the original plumber actually put the shutoff valves to the outside faucets underneath the lavatory in the basement allowing me to do this I want to make sure i'm not overlooking something obvious.

Moen has discontinued that dual temp hydrant.

The part I am having a problem with is that if they have dedicated valves under the sink, WHY would they be tied together somewhere in the ceiling? That would defeat the purpose for individual valves. Why not just connect the shutoff for the outside faucet to the hot side, after the tempering valve? You could use the outside faucet's discontinued valve to feed the tempering valve.