Estimating and Lost Time
When workers perform eight hours of work for eight hours pay, then there is no lost time. If there is an hour a day of lost time, that is 12.5 % lost time. Contractors must know the productivity of their employees. Lost productivity is real and must be accounted for in the bid summary.
Here are some project conditions that cause lost time:
- Late start times
- Longer than normal breaks
- Longer than normal lunch times
- Early quitting times
- Electricians waiting for material
- Clearance in and out of a secured facility
- Lack of sufficient quality tools
- Poor project planning and layout
- Poor productivity
- Poor staging of materials on the project site
This chart shows the impact and costs of lost time. The value columns are based on a $65 per hour labor rate.
| Lost Time (min.) | Loss Time % | # of Men | Weekly Value | Yearly Value |
| 30 | 6.25% | 5 | $812.50 | $42,250.00 |
| 60 | 12.50% | 5 | $1,625.00 | $84,500.00 |
| 90 | 18.75% | 5 | $2,437.50 | $126,750.00 |
| 120 | 25.00% | 5 | $3,250.00 | $169,000.00 |
| 30 | 6.25% | 25 | $4,062.50 | $211,250.00 |
| 60 | 12.50% | 25 | $8,125.00 | $422,500.00 |
| 90 | 18.75% | 25 | $12,187.50 | $633,750.00 |
| 120 | 25.00% | 25 | $16,250.00 | $845,000.00 |
| 30 | 6.25% | 75 | $12,187.50 | $633,750.00 |
| 60 | 12.50% | 75 | $24,375.00 | $1,267,500.00 |
| 90 | 18.75% | 75 | $36,562.50 | $1,901,250.00 |
| 120 | 25.00% | 75 | $48,750.00 | $2,535,000.00 |
| 30 | 6.25% | 200 | $32,500.00 | $1,690,000.00 |
| 60 | 12.50% | 200 | $65,000.00 | $3,380,000.00 |
| 90 | 18.75% | 200 | $97,500.00 | $5,070,000.00 |
| 120 | 25.00% | 200 | $130,000.00 | $6,760,000.00 |
Every contractor should know the impact of lost time among the field labor force. Study it, track it, and bid accordingly.
Remember, estimating is expensive, poor estimating is costly, and quality estimating is profitable.