ConstrCalc uses a small, transparent set of formulas. Every result the calculator produces is derived from these — no additional multipliers, no seasonal factors, no AI predictions.
Cost Chain
Subtotal = Materials + Labor + Equipment + Legal
Overhead = Subtotal × (Overhead% ÷ 100)
Profit = (Subtotal + Overhead) × (Profit% ÷ 100)
Grand Total = Subtotal + Overhead + Profit + Taxes
Worked Example
Materials $10,000 · Labor $8,000 · Equipment $2,000 · Legal $1,000 · Overhead 15% · Profit 10%.
- Subtotal = 10,000 + 8,000 + 2,000 + 1,000 = $21,000
- Overhead = 21,000 × 0.15 = $3,150
- Profit = (21,000 + 3,150) × 0.10 = 24,150 × 0.10 = $2,415
- Grand Total = 21,000 + 3,150 + 2,415 = $26,565
Per-Unit Metrics
Cost per ft² = Grand Total ÷ area (in ft²)
Cost per m² = Grand Total ÷ area (in m²)
Cost per Floor = Grand Total ÷ number of floors
Cost per Month = Grand Total ÷ project duration in months
These are derivations, not predictions. They tell you your unit rate — they do not forecast anyone else's.