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Planning sheet 01 · Transparent arithmetic · Planning estimate

Window area & solution calculator

Enter pane sizes, then the application rate and dilution from the actual product label. This sheet does no more than transparent arithmetic over your entered values — it never supplies a universal dose.

Pane row 1

Row area = width × height × panes × faces. Planned area adds your margin. Solution litres = planned area × entered rate ÷ 1000. A 1:n ratio splits solution into concentrate = solution ÷ (n + 1) and the rest water.

Worked example — fixed entered values

Base area
9.60 m²
Planned area (margin applied)
10.56 m²
Final solution
0.528 L
Concentrate
25 ml
Water
503 ml

Method notes

  • Uses the entered 50 ml/m² application rate — a planning estimate from your product label, not a universal dose.
  • Splits the solution with the entered 1:20 concentrate ratio. Check the label before mixing.

Worked example — fixed entered values

Four identical panes of 1.2 m × 1.0 m cleaned on both faces give 1.2 × 1.0 × 4 × 2 = 9.6 m². A 10 % planning margin lifts that to 10.56 m². An entered label rate of 50 ml/m² gives 10.56 × 50 ÷ 1000 = 0.528 L of ready-to-use solution, and an entered 1:20 ratio splits it into 0.528 ÷ 21 = 25 ml of concentrate (25.142857 ml unrounded) plus 503 ml of water (502.857143 ml unrounded). Displayed values are rounded; the calculation keeps the unrounded figures.

Blank worksheet

Width × height × panes × faces= base area (m²)
Base area × (1 + margin ÷ 100)= planned area (m²)
Planned area × label rate ÷ 1000= solution (L)
Solution ÷ (n + 1)= concentrate (L)
Solution − concentrate= water (L)

Related method context

Quantities here are transparent arithmetic over your entered values, so no external source is cited for the formulae themselves. Method context for what the quantities are used on sits in the window cleaning solution guide.