Outturn cost
The term ‘outturn’ or ‘out-turn’ refers to an amount achieved in a certain time, for example, an actual amount produced, or actual sales made. This is in contrast with the amount that might have been predicted or estimated. It is thought to be derived from, or related to, the term ‘turn out’.
The ‘outturn cost’ or ‘out-turn cost’ of a project is its actual construction cost. Generally this refers to the actual, total construction cost calculated at the end of the project, but it may also refer to the cost of a specific contract, or to costs incurred over a defined period. This contrasts with cost estimates, or target costs, which are calculations of the cost that is expected, or the cost that should be achieved.
This meaning of outturn cost is slightly confused by the use of terms such as ‘forecast outturn cost’, ‘estimated outturn cost’ or ‘target outturn cost’ which refer to the cost that is anticipated or should be achieved at the end of the project.
According to the Royal Institution of Chartered Surveyors (RICS), these outturn cost comprises: fixed costs, variable costs, variations, fluctuations and risk allowances.
- Fixed costs are costs that have been pre-calculated and agreed to be paid.
- Variable costs include; provisional sums, provisional quantities, prime cost sums and daywork allowances.
- Variations are alterations in the form of additions, substitutions or omissions from the original scope of works.
- Fluctuations are a way of dealing with inflation on large projects that may last for several years. The contractor is asked to tender based on current prices (prices at an agreed base date) and they are then reimbursed for price changes to specified items over the duration of the project (a fluctuating price).
- Risk allowances are financial allowances for works or services that are unknown in terms of quantity and specification, and are the client’s risk.
Cost prediction, Professional Statement, 1st edition, published in November 2020 by the Royal Institution of Chartered Surveyors (RICS), defines out-turn cost (‘final account’, ‘actual cost’ or ‘cost outcome’) as: ‘The known cost at the end of a project. Generally, it refers to the actual, total construction cost calculated at the end of the project, which includes the effects of any changes made to the design and the impact of any disruption. It may also refer to the costs incurred over a defined period, such as in life cycle cost.’
See also: Final account.
[edit] Related articles on Designing Buildings
- Balance sheet.
- Bill of quantities BOQ.
- Budget.
- Capital costs for construction projects.
- Construction costs.
- Contract conditions.
- Contract sum.
- Cost plans for construction projects.
- Cost reporting.
- Cost Value Reconciliations (CVR).
- Disallowed cost.
- Discounted cash flow.
- Elemental cost plan for design and construction.
- Final account.
- Prime cost sum.
- Quantity surveyor.
- Sunk cost.
- Types of cost.
[edit] External references
Featured articles and news
C20 Society; Buildings at Risk List 2025
10 more buildings published with updates on the past decade of buildings featured.
Boiler Upgrade Scheme and certifications consultation
Summary of government consultation, closing 11 June 2025.
Deputy editor of AT, Tim Fraser, discusses the newly formed society with its current chair, Chris Halligan MCIAT.
Barratt Lo-E passivhaus standard homes planned enmasse
With an initial 728 Lo-E homes across two sites and many more planned for the future.
Government urged to uphold Warm Homes commitment
ECA and industry bodies write to Government concerning its 13.2 billion Warm Homes manifesto commitment.
From project managers to rising stars, sustainability pioneers and more.
Places of Worship in Britain and Ireland, 1929-1990. Book review.
The emancipation of women in art.
Call for independent National Grenfell oversight mechanism
MHCLG share findings of Building Safety Inquiry in letter to Secretary of State and Minister for Building Safety.
The Architectural Technology Awards
AT Awards now open for this the sixth decade of CIAT.
50th Golden anniversary ECA Edmundson awards
Deadline for submissions Friday 30 May 2025.
The benefits of precast, off-site foundation systems
Top ten benefits of this notable innovation.
Encouraging individuals to take action saving water at home, work, and in their communities.
Takes a community to support mental health and wellbeing
The why of becoming a Mental Health Instructor explained.
Mental health awareness week 13-18 May
The theme is communities, they can provide a sense of belonging, safety, support in hard times, and a sense purpose.
Mental health support on the rise but workers still struggling
CIOB Understanding Mental Health in the Built Environment 2025 shows.
Design and construction material libraries
Material, sample, product or detail libraries a key component of any architectural design practice.
Comments
[edit] To make a comment about this article, or to suggest changes, click 'Add a comment' above. Separate your comments from any existing comments by inserting a horizontal line.