Builder, Estimator, and Quantity Surveyor Roles in the UK.
While a builder focuses on site execution and trade coordination, an estimator determines expected costs before work begins, and a Quantity Surveyor (QS) manages financial budgets, interim valuations, and contract accounts during construction.
Authored by Alexandr Vreme | Reviewed by Maksym Vasylkov
Published — Next review
Who this guide is for
Contractors, project managers, and clients seeking clarity on commercial roles. Scope: UK-wide.
Role Distinctions & Responsibilities
Understanding who does what ensures proper commercial oversight:
- Estimator: Measures quantities from drawings, builds up labor/material unit rates, gathers subcontractor quotes, and prepares tender returns.
- Quantity Surveyor (QS): Oversees contract terms, values variations, certifies monthly valuations, and agrees final accounts under JCT/NEC contracts.
- Builder / Project Director: Manages site logistics, safety compliance, material deliveries, and trade execution according to the estimate.
Miniature Example
On a £250,000 refurbishment, the estimator establishes the baseline £210,000 cost build-up. The QS manages monthly client payment applications (£30,000/month) and assesses scope change variations with the site builder.
Primary Sources & Further Reading
Official reference sources: GOV.UK Building Regulations, Legislation.gov.uk, and HSE CDM 2015 Guidance.
Explore related guides: Regulations & Market hub or meet our authors. Try the free Construction Estimator.