- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 07 Nov 2017
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.
 Find out more
 Related articles on Designing Buildings Wiki
Featured articles and news
Re-establishing human relationships with the natural world.
Post-occupancy evaluation of completed construction works.
Seven steps to defining a digital twin.
Achieving air tightness in buildings.
What are the benefits of smart homes for Millennial end-users?
How dynamic briefing can result in an efficient project.
Achieving sustainable roads funding in England.
Your chance to comment on the draft BS 851188 - flood resistance products and flood protection products.
Rebuilding could take 20 to 40 years.
RSHP’s high-rise residential towers win a tall buildings award for excellence.
BSRIA study reveals strong growth in 2018.