The DWV system should be tested with a minimum head of water for what duration?

The requirement to test a drain, waste, and vent (DWV) system with a minimum head of water for a duration of 15 minutes stems from industry standards and plumbing codes, which aim to ensure that the system is properly sealed and functioning as intended. Testing with water for an adequate period helps to identify any leaks or weaknesses that may cause future issues.

A duration of 15 minutes allows enough time for any gradual leaks to manifest. This testing duration is considered adequate to evaluate the integrity of both the horizontal and vertical elements of the DWV system, ensuring that all joints and connections can withhold the head of water without any sign of leakage. If shorter durations were used, minor leaks might not become evident, potentially leading to costly repairs later.

Additionally, following this recommended timeframe contributes to adherence to local plumbing codes, which often specify this duration as a minimum requirement to promote safety and reliability in plumbing systems. Therefore, testing the DWV system for 15 minutes is an essential practice for home inspectors to confirm the functionality and compliance of plumbing installations.