Compare calculators
Both calculators run independently β change the inputs on either side to compare results.
Plumbing
Plumbing Fixture Unit Calculator
Add up the drainage fixture units (DFU) for every toilet, sink, shower, bathtub, and appliance in a building to find the correct supply and drain pipe sizes per plumbing code. Essential for new construction, additions, or remodels.
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 | 5 | 5 |
| Result | Total Fixture Units (FU) | Peak Demand (GPM) |
| What it does | Add up the drainage fixture units (DFU) for every toilet, sink, shower, bathtub, and appliance in a building to find the correct supply and drain pipe sizes per plumbing code. Essential for new construction, additions, or remodels. | 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. |