A 20 mph zone is required by law to contain traffic calming measures placed at regular intervals to ensure compliance with the speed limit. Additional police enforcement is considered unnecessary.
Designation of a road as a home zone does not introduce any enforceable restrictions. The design of a home zone, and any measures implemented, should aim to achieve low vehicle speeds so that permitted activities can be enjoyed safely. The enforcement of any complementary restrictions, for example speed limits or parking, is a matter for the relevant authority, which may be the police or the local authority.