Weather Delay Cost Calculator

Weather delays hit construction predictably in most markets. This calculator sizes monthly exposure.

Weather days / month

Daily carry cost

Re-mobilization per event

Project months

Total weather cost

$193,200

Total days lost

Re-mobilization total

$67,200

How the math works

Total = (days lost × daily carry) + (events × re-mob cost). Re-mob assumed each ~1.5 days down.

Factor weather days into every construction schedule. Unpadded schedules look aggressive to GC and trigger sprint-to-finish that actually costs more. 5-10% schedule padding for weather pays off.

How to Use

Enter expected weather days/month.
Enter daily carry cost.
Enter re-mobilization cost.
Enter project months.
Read annual weather cost.

Frequently Asked Questions

Typical impact?

Southeast: 15-25 lost days/year. Midwest: 20-40 (winter bad). Pacific NW: 30-50 (wet). Southwest: 5-15. Plan around these ranges per market.

Force majeure?

Extreme weather qualifies; normal seasonal rain doesn't. Document with NOAA data. Extensions granted, but not always cost recovery. Fight for both.

Mitigation?

Schedule dirty work for better weather months. Cover/protect in-place work. Work 6 days during good windows. Winter-specific crews and materials.

Who owns this risk — sponsor or lender?

Construction risks are typically shared: hard-cost overrun owned by sponsor (via completion guaranty), soft-cost and delay risks shared per contract, force-majeure excused but bears owner carry cost. Document risk ownership in the loan agreement and GC contract before closing. Disputes get expensive when roles are unclear. Institutional deals spell out every allocation in writing.