Compare calculators
Both calculators run independently — change the inputs on either side to compare results.
Plumbing
Plumbing Fixture Unit Calculator
Calculates total plumbing fixture units (FU) for a building by summing standardized load values for toilets, sinks, showers, and tubs. Use it to size drain, waste, and vent (DWV) or water supply piping per code.
Fill in the required fields to see your result.
Plumbing
Fixture Unit Demand Calculator
Computes the total plumbing demand load in fixture units for toilets, sinks, showers, and appliances, then converts it to a peak flow estimate for pipe sizing. Use it when designing or auditing a building's water supply system.
Fill in the required fields to see your result.
Key differences
| Plumbing Fixture Unit Calculator | Fixture Unit Demand Calculator | |
|---|---|---|
| Category | Plumbing | Plumbing |
| Inputs required | 4 | 5 |
| Result | Total Fixture Units (FU) | Peak Demand (GPM) |
| What it does | Calculates total plumbing fixture units (FU) for a building by summing standardized load values for toilets, sinks, showers, and tubs. Use it to size drain, waste, and vent (DWV) or water supply piping per code. | Computes the total plumbing demand load in fixture units for toilets, sinks, showers, and appliances, then converts it to a peak flow estimate for pipe sizing. Use it when designing or auditing a building's water supply system. |