What are the normal flow conditions used when sizing mains and circuits in a residential system?

The normal flow conditions used when sizing mains and circuits in a residential system typically fall within the range of 2 to 4 feet per second (fps). This range is considered optimal because it provides a balance between efficient fluid transport and minimizing turbulence and noise within the piping system.

At this velocity, the fluid can move adequately through the pipes to supply fixtures and appliances without causing excessive pressure drops or potential issues such as pipe erosion or water hammer. Selecting a flow rate within this range helps ensure that the system operates effectively without compromising the longevity of the pipes or the efficiency of the overall plumbing system.

Other ranges mentioned do not align with standard practices for residential systems, as higher velocities could lead to increased wear and operational problems, while lower velocities might not sufficiently meet the demand for water supply.