Preliminaries: definition and example
The costs of running the site that do not belong to one item of work, such as supervision, welfare, access and site plant.
By Jack Butler-Kettle · Updated
Guidance for England and Wales. Check the contract, amendments and facts that apply to your job.
What it means in practice
Read this alongside NRM 2: Detailed measurement for building works and SCL Delay and Disruption Protocol.
Preliminaries are project-related costs that support delivery rather than one measured item of work. Some are time-related, such as supervision or hired accommodation; others may be fixed. That distinction matters when considering a change or delay because not every preliminary increases with duration.
Separate fixed and time-related costs in your records. Delay and disruption recovery can help explain which additional costs are connected to the event.
Worked example
The facts
A package has a one-off mobilisation cost and weekly supervision costs.
What happens
A delay extends supervision, but no second mobilisation takes place.
The subcontractor records the additional supervision separately from the original fixed cost.
What this shows
An extended duration does not justify charging every preliminary item again.