Irrelevant costs in construction
An irrelevant cost is an accounting term used to refer to costs that do not relate to whether or not a particular business decision is made. Irrelevant costs will be incurred regardless of the decision.
By identifying the irrelevant costs in relation to a particular business decision, unnecessary cost information can be removed from the decision making process, leaving only costs that are relevant to the decision (i.e. 'relevant costs' that will be affected depending on which option is selected). Time and effort can be saved by distinguishing between relevant and irrelevant costs when analysing decision options.
Typically, irrelevant costs include:
- Sunk costs: Costs that have already been incurred, and so are independent of any decision that might be made in the future.
- Committed costs: Costs that will be incurred in the future but must be paid regardless of any business decisions.
- Notional/non-cash costs: Depreciation, amortisation, and so on.
[edit] Related articles on Designing Buildings Wiki
Featured articles and news
A case study and a warning to would-be developers
Creating four dwellings... after half a century of doing this job, why, oh why, is it so difficult?
Reform of the fire engineering profession
Fire Engineers Advisory Panel: Authoritative Statement, reactions and next steps.
Restoration and renewal of the Palace of Westminster
A complex project of cultural significance from full decant to EMI, opportunities and a potential a way forward.
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.
The first line of defence against rain, wind and snow.
Building Safety recap January, 2026
What we missed at the end of last year, and at the start of this...
National Apprenticeship Week 2026, 9-15 Feb
Shining a light on the positive impacts for businesses, their apprentices and the wider economy alike.
Applications and benefits of acoustic flooring
From commercial to retail.
From solid to sprung and ribbed to raised.
Strengthening industry collaboration in Hong Kong
Hong Kong Institute of Construction and The Chartered Institute of Building sign Memorandum of Understanding.
A detailed description from the experts at Cornish Lime.
IHBC planning for growth with corporate plan development
Grow with the Institute by volunteering and CP25 consultation.
Connecting ambition and action for designers and specifiers.
Electrical skills gap deepens as apprenticeship starts fall despite surging demand says ECA.
Built environment bodies deepen joint action on EDI
B.E.Inclusive initiative agree next phase of joint equity, diversity and inclusion (EDI) action plan.
Recognising culture as key to sustainable economic growth
Creative UK Provocation paper: Culture as Growth Infrastructure.