Water Supply Fixture Units - WSFU vs. GPM and Liters/sec
Converting WSFU - Water Supply Fixture Units - to GPM.
The Water Supply Fixture Unit - WFSU - is defined by the American Uniform Plumbing Code (UPC) and is used to calculate the demand in water supply systems.
One WFSU for a singel unit corresponds to one GPM, or
- 1 WSFU = 1 GPM
The conversion can only be used for one or a few fixtures. When many fixtures are added up the number must be compensated due to the intermittent use of fixtures. The compensation is normally taken care of in probability curves or tables available for sizing water supply lines.
When special equipment or manifolds are sized the table below can be used to indicate the flowrate. Note that minimum flow rate can never be less than the fixture with the highest demand.
The tables below can be used to estimate the demand in the water supply system when the load in WSFU is known. There are tables for systems with and without flush valves.
Demand in Water Supply System without Flush Valves
| WSFU | Demand | ||
|---|---|---|---|
| GPM | ft3/min | liter/sec | |
| 1 | 3 | 0.41 | 0.19 |
| 2 | 5 | 0.68 | 0.32 |
| 4 | 8 | 1.07 | 0.51 |
| 8 | 12.8 | 1.71 | 0.81 |
| 15 | 17.5 | 2.3 | 1.1 |
| 30 | 23.3 | 3.1 | 1.5 |
| 50 | 29.1 | 3.9 | 1.8 |
Demand in Water Supply System with Flush Valves
| WSFU | Demand | ||
|---|---|---|---|
| GPM | ft3/min | liter/sec | |
| 5 | 15 | 2 | 1 |
| 7 | 19.8 | 2.7 | 1.3 |
| 10 | 27 | 3.6 | 1.7 |
| 15 | 31 | 4.1 | 2 |
| 20 | 35 | 4.7 | 2.2 |
| 30 | 42 | 4 | 1.9 |
| 50 | 50 | 6.7 | 3.2 |
Building Water Supply Diagram in gal/min
Building Water Supply Diagram in l/s
Related Topics
-
Water Systems
Design of hot and cold water service and utility systems with properties, capacities, sizing of pipe lines and more.
Related Documents
-
Cold Water Dwellings - Storage Capacities
Required cold water dwelling storage capacity - commonly used fixtures and types of buildings. -
Cold Water Storage per Occupant
Cold water storage for occupants in common types of buildings as factories, hospitals, houses and more -
Domestic Hot Water Service Systems - Design Procedures
Design procedures for domestic hot water service systems. -
Draining Systems - Main Vents
Vents in draining systems protects traps against pressure differences that could cause them to siphon or blow out . -
Drains and Sewers - Capacities vs. Size
Drainage Fixture Units (DFU) connected to building drains and sewers. -
Fixtures - Hot Water Content
Content of hot water in some common used fixtures - basins, sinks and baths. -
Hot and Cold Water Pipes Sizing
Recommended dimensions hot and cold water pipes. -
Hot Water Circulation System - Return Pipes
Hot water can be circulated through a return pipe if it's instantly required at the fixtures. -
Hot Water Consumption vs. Occupants
Consumption of hot water per person or occupant. -
Sanitary Piping - Drainage Fixtures Unit Loads
Maximum Drainage Fixture Unit - DFU - loads in sanitary piping systems. -
Water Supplies - Expected vs. Theoretical Summarized Demand
Calculating expected demand for water supply service lines. -
Water Supply due to Fixtures Water Requirements
Supply requirements for common fixtures. -
Water Supply Fixture Units WSFU
WSFU is used to calculate water supply service systems. -
Water Supply Lines - Sizing
Sizing water supply service and distribution lines based on Water Supply Fixture Units (WSFU). -
Water Supply Pipe Lines - Sizing
Sizing of water supply pipe lines. -
Water Supply Public Buildings
Required water supply to public buildings. -
Water Supply Systems - Online Design Application
Free online tool for designing water supply systems in buildings.
