I will be installing a 2 outlet thermostatic shower mixing valve in a new bathroom I'm putting in. I've read that by code, the valve must have isolation valves on the hot and cold supplies. My question is first, it this true, and if so, do the shut off valves need to be "dedicated" to the thermostatic valve. I have valves on the hot and cold supplies that can isolate the entire new bathroom. Do these count for the thermostatic valve, or do I need separate ones that can isolate the valve specifically?