The costs selected for any routine maintenance and asset renewal activities should be as reliable as possible. The selection of the maintenance strategy may be sensitive to the accuracy of this information.
A rigorous process should be developed for the collection and recording of cost data for the purposes of lifecycle planning. These cost data may be different from current contract rates because the data take other factors into account, such as overheads. Rates that are used should take into account inflation and be reviewed and updated as more cost information becomes available. The source of all cost data should be referenced.
The build-up of cost data is likely to include a number of assumptions, such as the inclusion of traffic management, contractor’s overheads, project design, and supervision costs. Such information may not be directly available from unit rates, which may be obtained from sources such as term maintenance contracts or framework contracts. Therefore, care needs to be taken in building up the rates in order to understand the item coverage.