Prime cost in construction contracts
In general terms, the ‘prime cost’ is the sum of the direct cost of materials and labour associated with a production process. It is the direct cost of the inputs to a process that are necessary to create the output. If the prime cost can be lowered, the process may become more profitable.
In construction, the term ‘prime cost sum’ (PC sum) is an allowance for the supply of labour, plant and materials to be provided by a contractor or supplier that will be nominated by the client. The allowance is exclusive of any profit mark up or attendance (such as material handling, scaffolding and rubbish clearance etc) by the main contractor. See prime cost sum for more information.
Prime cost contracts (sometimes referred to as cost plus contracts or cost reimbursement contracts) are contracts in which the contractor is paid the prime cost (the actual cost of labour, plant and materials) and a fee for profit and overheads.
Prime cost contracts are used where an early or immediate start on site is required even though design information is not complete, for example for urgent alteration or repair work. See Prime cost contract for more information.
Adjustments may be permitted to prime costs during the period of a contract to allow for inflation (fluctuations).
[edit] Related articles on Designing Buildings Wiki
Featured articles
Check out some of the best features and news from Designing Buildings as well as key stories from around the web.
The Building Safety Regulator announces a call for evidence.
Government approach could undermine delivery and regeneration.
World's first mass timber data centre.
The overlooked environmental aspect of data centre development.
Introduction to radon awareness
New technical information sheet published by CIOB.
Updated supplier guide can help electrical contractors engage with NHP.
CIAT confirm the winners of the 2026 architectural technology awards.
Government launches a one stop shop for flood preparedness.
Sir Edwin Lutyens: Britain's greatest architect? Book review.
CIOB publishes free template to help assess and manage risks.
ECA's reflections on Party Conference season
Burnham wants to be confident of winning before asking for a fresh mandate.
New Chief Construction and Scientific Adviser
Sergio Cavalaro, Professor of Infrastructure Systems at Loughborough University.
Building safety levy for England
CIAT publish estimator tool for members.
Comments
Construction on this page has been spelt incorrectly! - well spotted, this has been fixed