Fixture Unit Demand Calculator vs Greywater Recycling Calculator
Two calculators for the same neighbourhood of questions. Here is what each measures, what you feed in, and where you'd reach for one over the other.
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.
- Answers
- Peak Demand (GPM)
- Inputs
- Water Closets/Toilets, Lavatories/Sinks, Showers, Major Appliances, Usage Factor
Greywater Recycling Calculator
Estimate your household's weekly greywater output from showers, sinks, and laundry, then see how many gallons are available for garden irrigation or toilet flushing after system losses. Use it when sizing a greywater recycling setup.
- Answers
- Weekly Greywater Available (gallons)
- Inputs
- Household Size, Weekly Laundry Loads, Daily Shower Usage, Bathroom Sink Usage, System Efficiency
At a glance
| Fixture Unit Demand Calculator | Greywater Recycling Calculator | |
|---|---|---|
| Category | Plumbing | Water Usage |
| Answers | Peak Demand | Weekly Greywater Available |
| Inputs | 5 | 5 |
| Result unit | GPM | gallons |
When to use each
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.
Estimate your household's weekly greywater output from showers, sinks, and laundry, then see how many gallons are available for garden irrigation or toilet flushing after system losses. Use it when sizing a greywater recycling setup.