Schedule Delay Days Rate

A calendar delay KPI broader than weather-only delay %. Not SPI/SV—those are earned-value tools on the Professional hub.

Delay % = total delay days ÷ planned workdays × 100.

Tip: Keep “Delay Days” and “Planned Workdays” on the same basis (period, units, and population) before calculating Schedule Delay Days Rate.

Cluster: Construction hub · Safety TRIR · CPI · SPI · Percentage guide

Schedule delay days rate compares total delay days (all causes) to planned workdays.

Enter delay days and planned workdays for the same window.

Total delay days in the period
Planned workdays

Schedule Delay %

Understanding Schedule Delay Days Rate

How we calculate. Delay % = total delay days ÷ planned workdays × 100. The form uses the same arithmetic as the worked examples on this page. See our methodology and accuracy policy.

Real-world scenario: A typical Schedule Delay Days Rate case uses delay days 9 and planned workdays 60. Enter the same figures below to reproduce the worked path.

What is Schedule Delay Days Rate?

A calendar delay KPI broader than weather-only delay %. Not SPI/SV—those are earned-value tools on the Professional hub.

  • All-cause delay days (or labeled subset)
  • Same workday basis
  • Cross-link weather delay % for weather-only

The Formula

Schedule Delay Days Rate
Delay % = (Delay days ÷ Planned workdays) × 100

Worked Example

Scenario: 9 delay days of 60 planned workdays.
Step 1: 9 ÷ 60 = 0.15
Step 2: × 100 = 15%
Answer: Schedule delay rate is 15%.

Common Use Cases

  • Schedule narrative: delay intensity
  • Owner reports: lost workdays
  • Risk reviews: delay vs plan

Pro Tips

  • Code delay causes
  • Avoid double-counting concurrent delays
  • Use SPI for EV schedule performance

Limitations: Schedule Delay Days Rate results are educational construction planning aids—not engineering, safety, legal, or cost-estimating advice. Confirm definitions with your project controls, safety, and contract documents. For earned-value SPI/CPI see the Professional hub.

FAQ

Different from weather delay %?

Weather delay % is weather-only. This tool uses total delay days—narrow the numerator if you want a cause-specific rate.

What if planned workdays is 0?

Delay % is undefined—enter a positive planned workday count.

Authoritative References

For construction project controls and safety rate concepts, consult:

  • OSHA — workplace safety resources
  • PMI — project management practices
  • AIA — contract and project delivery context