Sylvan. Tut Tut. Although the USA being the only civilsed country in the world that has developed balancing & temperature control since 1965, it is also not law it seems to be a licensed Plumber to carry out Plumbing and the fragmentation & different Code areas defy my uncivilised brain.
In Australia it is LAW to be a Plumber & no person is allowed to interfere with plumbing unless they are licensed. It is also LAW to install tempering valves to any new installation.
We dont seem to have the *********** you often talk about but hey they create work for you dont they?
In Australia we work to one Standard although in each different State there is slightly different methods of interpretation.
Bob the Uncivilised Plumber