Why Use a Pipe Sizing Calculator?

Proper pipe sizing isn’t just matching a diameter to flow. It’s the difference between efficient systems and
wasted energy, material overrun, and noise or erosion issues. The Pipe Sizing Calculator applies
ASHRAE-style velocity and pressure-drop criteria so you can:

• Improve efficiency by minimizing pumping power and friction losses.
• Reduce costs by avoiding oversizing and unnecessary material/labor.
• Build reliability—control velocity to limit noise, erosion, and wear.
• Work faster with defensible results you can share with teams and clients.

How the Calculator Works (Inputs & Outputs)

Inputs: material (e.g., Sch 40 steel, copper, PVC), flow rate (GPM), target velocity (ft/s), run length, and fittings.

Outputs: Recommended Nominal Pipe Size (NPS), velocity, Darcy head loss, and pressure loss per 100 ft—so you can validate your selection instantly.

What’s Inside the 17-Tab Spreadsheet

The companion spreadsheet includes ready-to-use reference data for fast lookups and cross-checks:

1. S40-Crit – Schedule 40 steel sizing criteria, flow vs. velocity & pressure drop.
2. Cu-PVC – Copper & PVC sizes, IDs, and flow capacity references.
3. S80-XS – Schedule 80 & Extra-Strong steel reference data.
4. Fe-Al-Br – Iron, aluminum, brass pipe properties.
5. Haz-Will – Hazen-Williams constants and friction references.
6. Fittings – Equivalent length tables for elbows, tees, etc.
7. Valves – Loss coefficients by valve type and size.
8. Fluids – Fluid properties (density, viscosity) for accurate calcs.
9. Steam-Condns – Steam condensate return sizing.
10. Steam-Charts – Steam P-T tables and flow data.
11. Natural-Gas – Gas piping charts: flow, velocity, allowable ΔP.
12. FixtUnits – Fixture unit tables for domestic water demand.
13. Sanitary – Sanitary drainage sizing references.
14. Vents – Vent pipe sizing and code-style references.
15. Storm – Stormwater drainage pipe sizing.
16. CHW-Schematic – Example chilled water distribution schematic.
17. Plant-Schematic – Plant-level piping schematic for quick reference.

Who Benefits from This Toolkit?

• Mechanical Engineers & HVAC Designers—verify sizes quickly and defensibly.
• Plumbing Contractors & Designers—reduce guesswork and callbacks.
• Energy Modelers & Consultants—align model inputs with real-world tables.
• Students & Trainees—learn standards with professional-grade tools.