Project-specific costs needed to manage and deliver the works that are not usually measured as permanent construction, such as site setup, supervision and welfare.
Why it matters
Preliminaries often depend on programme duration, access and logistics, so they should be reviewed when those assumptions change.
Example in practice
The estimate includes site management, welfare, temporary fencing and waste facilities for the planned duration.
Use the term carefully
State the scope, amount, adjustment method or contract meaning whenever this term could change who carries cost or risk.