supply lines 66 68 and temporary water shut off valves 70 72 are provided shims not shown in fig4 may be used to provide a comfortable fit between frame 12 and wall studs 60 62 also as shown in fig4 several pipe nipples 74 are inserted into the spray mountings 20 these pipe nipples 74 are used to prevent debris from entering into spray mountings 20 and the piping configuration 18 while a wall is being built to close in the plumbing system 10 of the invention once a wall is constructed in front of the prefabricated plumbing system or wall system 10 the pipe nipples 74 can be removed more about which is discussed hereinbelow referring to fig5 a the wall studs 60 62 may be about 2 inches thick and 4 inches wide support frame 12 may have a depth of 3 inches so that the wall studs 60 62 overhang frame 12 by about 1 inch as also shown in fig5 a pipe nipples 74 also extend beyond wall studs 60 62 for their easy removal from spray mountings 20 not shown in fig5 a fig5 b shows that a cement board 76 may be nailed to studs 60 62 and that this cement board 76 may contain a finish material such as tile marble or granite indicated at reference number 77 preferably the finished wall thickness ranges between 4.