Wondering how much does a renovation cost in the UK? It’s one of the biggest questions when planning a home extension or renovation. Many homeowners assume that only a builder can give a reliable price — but architects can also provide valuable cost guidance from the very start.
In this guide, we explore how an architect can help you understand renovation costs, compare the traditional and design and build routes, and explain the importance of having a contract with your builder for cost certainty.
Image above by William, architect on Design for Me. See more of his profile and shortlist him for your project here.
Can an architect estimate renovation costs in the UK?
Yes — although they’re not quantity surveyors, experienced architects can give a good indication of renovation costs in the early stages of a project. They often draw on data from past builds, benchmark cost per square metre figures, and their familiarity with local market rates to guide your design within budget.
For example, in another post, we have shared real-life case studies showing typical extension and renovation costs per square metre. This data helps both architects and homeowners gauge what’s financially realistic before any work begins.
A good architect will use this information to tailor your project, suggesting design options and materials that meet your style and budget goals. This level of insight is particularly useful if you’re trying to avoid overspending during the design phase.
Should I get a quote from builders before hiring an architect?
This is a common question — and the answer is usually no. Builders need detailed architectural drawings and specifications to give accurate quotes. Without this information, you’re likely to receive broad ballpark estimates that don’t reflect the final cost.
Instead, start with an architect. They’ll help you develop the brief, create drawings, and ensure that everything is ready for tender. As discussed in another article, Hiring an architect first leads to fewer surprises, smoother planning, and more accurate cost control later on.
Traditional architect route vs design and build: which gives more cost certainty?
When budgeting for your renovation, choosing the right project route is key. Two common approaches are:
- Traditional architect-led route – Your architect designs the project and helps you tender to several builders. This gives you greater creative control, but costs are only finalised after the design stage, so there may be more variability.
- Design and build – One company manages the entire process, from design through to construction. This often means a fixed price can be provided earlier, offering more cost certainty — but potentially less flexibility in design choices.
You can read more on this comparison in Design for Me’s article: Pros and cons of design and build.
Why a builder contract is essential for cost certainty in renovations
Having a formal written contract with your builder is essential — especially if you want to protect your budget and timeline. A good contract will set out:
- The total project cost and payment schedule
- What is and isn’t included in the scope of work
- Penalties or clauses for delays or changes
- Procedures for handling unexpected costs
An architect can guide you through this process. They can recommend standard contract templates (such as a JCT contract), ensure the right clauses are included, and even act as a contract administrator — meaning they’ll oversee the build, certify payments, and manage any changes on your behalf.
This role is vital in keeping your project on track financially. Learn more in Design for Me’s guide: Do I need a contract with my builder?
Final thoughts: can an architect help manage your renovation budget?
If you’re asking, can an architect tell me how much a renovation will cost? — the answer is roughly, yes, within reason. While they won’t give you a fixed builder quote on day one, their experience and cost awareness make them key to designing a project that fits your budget.
Working with an architect also gives you access to better planning, smarter design solutions, and professional contract administration — all of which help deliver your project on time and on budget.
Looking for a trusted architect near you?
Looking for a trusted architect near you? Design for Me matches homeowners with independent architects for extensions, renovations, and new builds.
Emily Design for Me
