wrote in message
oups.com...
all the water lines inside my home are 1/2 inch, although the outdoor
supply is 3/4

we have a single copper 1/2 inch line servicing the bathroom. it
supplies the toilet sink and finally the shower

if someone flushes the toilet while someone is in the shower they get
burned.

the cold water pressure and flow drops nearly all goes to the toilet.

my fix is add a hot and cold PEX lines just for the shower from the
hot water tank area.

i think this would decrease the problem a lot.

It may help, but will not cure the problem. Best solution is to install an
anti-scald valve. You can adjust it to a maximum temperature and it will
not go above that if the water is turned on. Keep in mind, if someone in
another room turns on the hot water, you may get a cold shower, but not the
other way around. Another advantage is you cannot accidentally turn the
hot to a scalding temperature. Especially good with kids or elderly in the
house.

For more money you can get a thermostatic faucet that will keep a constant
temperature, but will have some decreased flow if another faucet is opened.