IS 2065 provides comprehensive guidelines for the design, layout, and installation of water supply systems in buildings. It details the methodologies for pipe sizing using fixture units, outlines water storage requirements, and specifies best practices for distribution networks and plumbing installations.
Provides comprehensive guidelines for the design, installation, and maintenance of water supply, plumbing, and drainage systems in buildings.
Quick Reference Values
Maximum velocity in indoor distribution pipes1.5 to 2.4 m/s
Minimum residual head for standard taps1.2 m
Minimum residual head for flush valves10 m
Testing pressure for water supply mains1.5 times maximum working pressure
General combined storage capacity requirement50% to 100% of daily requirement depending on supply hours
Key Formulas
Hazen-Williams Formula: V = 0.849 C R^0.63 S^0.54 — Used for calculating friction losses in pipes
Q = A × V — Continuity equation for determining pipe diameter
Practical Notes
Always use IS 2065 in conjunction with IS 1172; IS 1172 provides the per-capita water demand, while IS 2065 guides the engineering layout and pipe sizing.
Pipe sizing should strictly account for peak hour demand and probable simultaneous demand (fixture unit method), not just average daily flow.
Ensure adequate residual pressure is maintained at the highest and farthest fixtures, especially if utilizing flush valves instead of flush tanks.