Hi Ia,

You can put a 25 psi rated in-line PR (less $)from HD in your system. Either in the pvc line leading to your poly line or just before your poly-line. You could do the same with a house rated 40 psi regulator but it isn't necessary. A in-line filter is also recommended. Your irrigation tie-in must be before the house pressure regulator to be 85 psi. The 85 psi would be fine for your sprinkler zones. You can power more sp heads per zone. Your contractor should have set a 25 psi PR before the poly-line zone. Have a cold icy Mai Tai and have the installer come back and do it for free. Aloha