General Conditions Burn Calculator

GC spend scales with project duration.

Monthly GC spend

Planned months

Extended months

Total GC cost

$3,060,000

Extension cost

$540,000

Planned GC

$2,520,000

How the math works

Planned GC = monthly × planned months. Extension = monthly × extended. Total = sum.

$180k × 14 = $2.52M planned. + $540k extension = $3.06M total. 21% over budget.

How to Use

Enter monthly GC spend.
Enter planned months.
Enter extended months.
Read total GC and extension cost.

Frequently Asked Questions

What are GCs?

General Conditions: site supervision, superintendent, safety, permits, small tools, temporary site services (electric, water), site trailers, cleanup. Typically 6-12% of direct costs for typical construction. Scales with project duration — longer project = more GCs.

Budget ranges?

Class A commercial: 8-12% of direct cost. Multi-family: 6-10%. Industrial: 4-8%. Renovations: 10-15%. Historical/complex: 12-20%. Small projects (<$5M): can reach 20%. Size and complexity drive percentages.

Managing?

Fixed-fee GCs (negotiated upfront) vs % of direct. Size correctly for project duration. Audit GC spend monthly. Tight extension language — owner shouldn't pay extended GCs if delay is contractor's fault. Material on long projects.

How often should I rerun this?

Rerun this calculator whenever inputs change materially — new rent roll data, rate moves, loan balance updates, or quarterly operating data. For active deals, monthly refresh is typical. For stabilized assets under monitoring, quarterly is fine. Treat the output as a decision tool, not a one-time answer — market conditions evolve and so should your analysis.