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THE FEUTEX TOOLKIT

Shower Water and Hot-Water Share

Estimate mixed water use and the hot-water share from measured temperatures.

Household workspace● Runs in your browser
01 Your input
02 Your result
View or copy raw result data
FormulaTotal = flow*minutes*people; Hot water = flow*minutes*people*(mixed-cold)/(hot-cold); Cold water = flow*minutes*people*(hot-mixed)/(hot-cold)

Worked example

Inputs

Flow
8 L/min
Minutes
7 min
Cold
10 °C
Hot
60 °C
Mixed
40 °C
People
4 people

Expected results

Total
224 L
Hot water
134.4 L
Cold water
89.6 L

Load the example in the workspace to reproduce these results. Display rounding does not change the underlying calculation.

How to use this tool

  1. Enter the measured quantities and your own planning assumptions.
  2. Review all calculated outputs and the stated limitations.

Try this example

{
  "flow": 8,
  "minutes": 7,
  "cold": 10,
  "hot": 60,
  "mixed": 40,
  "people": 4
}

Accuracy and scope

Ideal mixing balance only, not a temperature recommendation. Ignores pipe losses and heater recovery.

Is my data uploaded?

This tool runs locally in your browser. Input and output are not sent to a processing server. Copy or download your result before leaving the page.