Lang Factor Construction Cost Estimator

Estimate preliminary total process-plant cost from the purchased or delivered cost of major equipment.

Estimate basis

This is a screening-level equipment-factored estimate. Enter the cost of major process equipment on a consistent purchased or delivered-cost basis. The selected factor is intended to account approximately for the rest of the installed plant cost.
Mixed solid-fluid: for processes with significant solids handling plus liquid or gas processing.
No exchange-rate conversion is performed. Enter every equipment cost in the selected currency.

Major equipment costs

Add the major equipment items included in your estimate basis.

Results

Estimated total plant cost
Major equipment cost
Lang factor used
Estimated non-equipment portion

Equipment subtotal

EquipmentQtyUnit costSubtotal

Equation and factor selection

Estimated total plant cost = Lang factor × Σ(major equipment cost)
  • 3.10 — Solid processing: primarily solids handling and solids-processing equipment.
  • 3.63 — Mixed solid-fluid processing: substantial solids handling together with liquid or gas processing.
  • 4.74 — Fluid processing: primarily liquid and gas processing, where piping, instrumentation, and related installation costs tend to be more significant.

Classic Lang factors are intended for early, equipment-factored estimates. Actual project cost depends on location, labor, materials of construction, pressure, plant complexity, utilities, site work, offsites, escalation, contingency, and the cost basis used for the equipment list. Use project or company historical factors when available.