What is a construction estimate?
A construction estimate is an informed prediction of the costs required to complete a building project. It is not a quotation or a fixed price — it is a calculated assessment based on measured quantities, known rates, and professional judgement.
Who uses estimates
Builders, contractors, quantity surveyors, and project managers prepare estimates at different stages. Clients use them to decide whether to proceed. Main contractors use them to price tenders. Subcontractors use them to price their packages.
What an estimate contains
Every estimate starts with a scope of works. Quantities are measured from drawings or site measurements. Each item is priced using labour, materials, and plant rates. Subcontractor quotations are added. Preliminaries, overheads, and profit are included. The total becomes the estimated cost.
Miniature example
A builder measures 40 m² of brickwork for a garden wall. They calculate: 40 m² at 60 bricks per m² = 2,400 bricks at £0.65 each for materials. Labour: one bricklayer at £25/hour, one labourer at £18/hour, estimating 2.5 hours per m². Materials £1,560 + labour £430 = estimated cost £1,990 before overheads and profit.
Common mistakes
- Presenting an estimate as a fixed price without clear exclusions
- Omitting preliminaries such as skip hire, welfare facilities, or site supervision
- Using outdated rates that do not reflect current material or labour costs
- Forgetting to state what is excluded so the client understands the scope
Related guides and tools
Learn about levels of estimate accuracy and the different estimate document types. Try the Construction Estimator or Budget Estimate generator to build your own.