My house is plumbed so I can shut off all of the water to the inside of the house and garage, (slop sink, washing machine, water heater, and water softener). But still allow for water to flow for all of the outside irrigation. This was something the previous owner had done. (It has become a fairly common plumbing rework out here).
Naturally, if I shut it off at the main at the street, it kills everything. Which is what I had to do to complete my project, because I was tapping into an outlet that was plumbed for irrigation when the home was built. (Which is the reason you see wires wrapped around the pipe for the irrigation timer).
But out here it should be made code that all houses should be plumbed this way. Reason being is we have a lot of snowbirds that live here. And or retired people who travel a lot. They own houses that sit empty several months out of the year. (Usually from early April through Summer until late September or early October).
They have to leave their water on, otherwise all of their outside plants and trees will die. So while their house sits unoccupied, if their icemaker, RO system, or washing machine hoses fail, their entire house will flood. (Plumbing is only as strong as the weakest link).
Or if they get a pin hole leak in any inside or attic plumbing or faucet connection, it will also flood. Water damage from plumbing failures costs the insurance industry the most of any other type of damage in homes today.
By splitting the plumbing from inside and outside, this danger can be eliminated.
