When should water supply piping be leak-tested?

Water supply piping should be leak-tested before the walls are closed to ensure that there are no leaks or issues that could cause problems once the walls are sealed. Conducting the leak test at this stage allows for easy access to the piping system, making it easier to identify and repair any leaks found during the test. If leaks are discovered after the walls are closed, it can be very difficult and costly to make the necessary repairs, as it would often involve significant demolition work. Therefore, performing the test before the walls are closed is a critical step in the plumbing installation process to ensure the long-term integrity and functionality of the system.