Water Supply Pipe Sizing
PROSize water supply pipes by fixture unit loading and velocity limits per AS/NZS 3500 or UPC.
BEng Mechanical Engineering (Hons), CMIOSH, LEEA Member
Mechanical engineer and certified lifting equipment examiner with 18 years in heavy industry, structural steelwork, and crane operations across construction and resources sectors.
1 April 2025
Professional verification required
These calculations are provided for estimation and educational purposes only. Results must be verified by a suitably qualified and licensed engineer before use in any design, specification, or construction context. Numly accepts no liability for decisions made on the basis of these results.
Size pipes so residual pressure ≥ 100 kPa at any fixture; max velocity 3 m/s cold, 2 m/s hot.
Standards New Zealand
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