'Finish to Start Links lead / lag' quality metric
Use this metric to check the proportion of Finish-to-Start links that have no lead/lag. The Chartered Institute of Building (CIOB) standard states that Finish-to-Start links must not have lead/lag, as the offset this represents cannot be progressed and quantified.
With the pass and fail boundaries set to 100.00%, this metric meets the requirements of CIOB stress test 3 (No lag on FS links).
Examples of Finish-to-Start links with lead/lag
In the following illustration, the Finish-to-Start link between Task 2 and Task 3 has 3d lag. This link would fail this metric:
In the following illustration, the Finish-to-Start link between Task 2 and Task 3 has 1d lead time. This link would fail this metric:
You can change the impact that this metric has on the weighted total result of a quality check by entering a factor by which the quality metric should be multiplied in the Weighting field. For the weighting to have any effect, a quality check must have more than one quality metric.
Pass and fail criteria
| Pass or fail? | Criteria |
|---|---|
| Pass |
A project passes this metric if the percentage of Finish-to-Start links that have no lead/lag is greater than or equal to the pass boundary percentage.
For example, if the pass boundary was set to 100.00%, a project would pass this metric if 100.00% of Finish-to-Start links had no lead/lag. |
| Fail |
A project fails this metric if the percentage of Finish-to-Start links that have no lead/lag is less than the fail boundary percentage.
For example, if the fail boundary was set to 100.00%, a project would fail this metric if less than 100.00% of Finish-to-Start links had no lead/lag. |
| Neither pass nor fail | If the percentage of Finish-to-Start links that have no lead/lag falls between the pass and fail boundary percentages, the result is neither a pass nor a fail, but somewhere in between. |
Suggested settings to meet the requirements of CIOB stress test 3 (No lag on FS links)
- Pass boundary: 100.00%. A project will pass this metric if no Finish-to-Start links have lead/lag.
- Fail boundary: 100.00%. A project will fail this metric if any Finish-to-Start links have lead/lag.
The following table shows whether some example projects would pass or fail this metric using these settings:
| Percentage of Finish-to-Start links with no lead/lag | Pass or fail? |
|---|---|
| 0.00% | Fail |
| 50.00% | Fail |
| 99.99% | Fail |
| 100.00% | Pass |
Does the metric force a project to be rescheduled?
No.
Suggested actions if a project fails this metric
If a project fails this metric, select the metric in the Quality Check Results dialog and click Show Failing Tasks to view the links that have failed the metric, together with the tasks at either end of the links.
You could take the following actions to remedy the failing links:
- Examine the links to determine whether it is appropriate for them to have lead time. If a link has inappropriate lead time, edit the link and remove the lead time.
- Examine the links to determine whether it is appropriate for them to have lag. If a link has inappropriate lag, edit the link and remove the lag.
- If it is appropriate for a link to have lag, consider removing the lag from the link and creating an additional task that represents the lag time. For example, if a 'Pour concrete' task is linked to a 'Drainage works' successor task by a link with 2d lag, with the lag representing the time it takes for the concrete to cure, consider removing the lag from the link and adding a 2d long task called 'Cure concrete' between the 'Pour concrete' and 'Drainage works' tasks, as illustrated below.
The link with lag:
Can be replaced with a 2d long task:
