PIPE
SIZING
Domestic water, hydronic, DWV, fuel gas, and storm — with the code book YOU answer to. Pick IPC or UPC and the edition; fixture units, capacities, and section numbers switch to match. Every result shows its math and cites its table.
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Code tables where the code governs. Real hydraulics where it doesn't.
Where the code is the law — fixture units, DFU capacities, minimum slopes — this calculator uses the values from the code family and edition you selected, cited to the exact table. Where the code leaves it to engineering — pressure-pipe friction, hydronic loops — it computes real hydraulics: Hazen-Williams or Darcy-Weisbach with Colebrook, using actual pipe inside diameters per the ASTM dimension standards, not nominal guesses.
Five calculators, one honest rule
Domestic water: WSFU totals → Hunter's curve → Hazen-Williams at your velocity limit. Hydronic: BTU/hr and ΔT → GPM → friction-rate sizing per ASHRAE guidance. DWV: DFU totals → branch, stack, or building-drain capacity at your slope, with the code minimum slope enforced. Fuel gas: longest-length method with the NFPA 54 / IFGC low-pressure equation. Storm: rainfall × roof area → leader and horizontal drain capacity. The rule everywhere: requirements cite the code section; rules of thumb are labeled guidance — never dressed up as code.
Editions matter
Your inspector doesn't enforce "the IPC" — they enforce a specific edition, possibly amended. That's why the edition selector exists and why citations name the year. If your jurisdiction amends a table, the citation tells you exactly what to double-check.
Detailing MEP in Revit or Fusion?
Fulcrum builds tools that do this class of grunt work inside your model — and the free ones stay free.
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