Sprinkler Density–Area Calculator

Plan hydraulically remote areas with confidence. Set hazard presets or custom values, factor hose allowances, and include a safety margin. See total demand, operating sprinklers, per‑head flow, and end‑head pressure instantly. Works in US or metric units and supports printable reports. Built for rigorous sprinkler layout checks and quick what‑if analysis. Includes presets, interpolation, and detailed guidance for compliance review.

Inputs

Preset values populate the density and area fields; adjust as needed.
Typical: 9.29 m² (100 ft²), 11.15 m² (120 ft²), etc.
Common: 5.6 (≈80 metric), 8.0 (≈115 metric), 11.2 (≈161 metric).
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Results

Operating sprinklers 15
Per‑head flow 15.00 gpm (56.78 L/min)
End‑head pressure 7.17 psi (0.495 bar)
Flow (without hose) 225.00 gpm (851.72 L/min)
Total system demand 275.00 gpm (1,040.99 L/min)
Calculations assume uniform discharge equal to density × coverage. For detailed hydraulic calculations (pipe friction, elevation, C‑factor), use a full hydraulic model.

FAQs

1) What does the density–area method represent?

It specifies a design density (flow per unit area) applied over a defined remote area. The product sets the base water demand used for hydraulic calculations.

2) How are operating sprinklers estimated?

The calculator divides the design area by the coverage per sprinkler and rounds up to the next whole head.

3) How is end‑head pressure calculated?

Per‑head flow equals density × coverage. The required pressure is (q/K)² using the selected K‑factor. Results are shown in psi and bar.

4) What values should I use for coverage?

Use the effective coverage area per sprinkler based on spacing and listing. Common values are 100–144 ft² (≈9.29–13.4 m²) for many occupancies; verify with product data and codes.

5) Can I input metric units?

Yes. Toggle units to metric. The tool converts all inputs and shows metric and US outputs side by side.

6) What about hose stream allowance?

Enter a value appropriate for the hazard and standard in use. The calculator adds it to the base flow before any optional safety margin.

7) Is this a replacement for full hydraulic modeling?

No. This is a planning aid for the density–area step. Detailed pipe sizing, friction loss, elevation head, and pump curves require a comprehensive hydraulic analysis.

Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.