Most advice on choosing a builder starts with getting three quotes and checking they have insurance. That’s sensible advice, but it rarely tells you which contractor is actually the right fit for your project.
The better question is whether they have the experience, systems and people to deliver your particular build – and whether you’ll be comfortable working with them for the next several months.
Have they completed projects like yours?
Experience isn’t one-size-fits-all.
A contractor who builds twenty loft conversions every year may be exceptionally good at that type of work but have very little experience renovating a listed farmhouse or carrying out structural alterations to a period property.
Ask when they last completed a project similar to yours, how many they’ve undertaken in recent years and whether you can visit a completed project, with the homeowner’s permission. Photographs are useful, but seeing the finished workmanship in person often tells you far more.
Recent experience can be just as valuable as the total number of projects completed. Construction standards, regulations and even the people within a business change over time.
Make sure their expertise matches your project
Not every project requires a specialist contractor.
A straightforward extension to a modern house can usually be undertaken by any competent and well-managed general builder. Paying for specialist expertise you don’t need may simply increase costs without adding value.
Some projects, however, demand more specific knowledge.
Many buildings constructed before the early twentieth century have solid masonry walls, often with no damp proof course, and manage moisture very differently from modern cavity wall construction. Using incompatible materials or inappropriate repair methods can lead to trapped moisture, damp and unnecessary deterioration, particularly in historic buildings.
If you’re renovating a listed building or period property, ask about the contractor’s experience with traditional construction methods, lime mortars, conservation work and working alongside conservation officers or specialist consultants.
Do they have the capacity to give your project the attention it deserves?
A contractor can have an excellent reputation and still be the wrong choice if they’re managing more work than they can realistically deliver.
Ask how many projects they’ll be running alongside yours, who will be responsible for your project day to day and who you’ll contact when decisions need to be made.
Some companies successfully manage multiple projects with dedicated site managers. Others deliberately limit the number of projects they undertake to maintain closer involvement throughout the build.
Neither approach is inherently better. The important thing is understanding how your project will be managed and deciding whether that suits your expectations.
Understand who will actually be carrying out the work
Some contractors employ their own tradespeople directly, while others manage teams of specialist subcontractors.
Again, neither approach is right or wrong. Many excellent projects are delivered using carefully selected subcontractors.
What’s important is understanding who will be working in your home, who is responsible for quality control and who remains accountable if something doesn’t go according to plan.
Check the paperwork carefully
Professional contractors should be happy to provide evidence of their insurance.
Typically this includes:
- Public Liability Insurance
- Employers’ Liability Insurance (where staff are employed)
- Details of who is responsible for insuring the works during construction. Many contractors carry Contractors’ All Risks insurance, although arrangements can vary between projects
Don’t be afraid to ask to see the certificates and check that they’re current.
Membership of recognised industry organisations can also provide additional reassurance.
The Federation of Master Builders independently assesses applicants before membership is granted, while TrustMark is a Government-endorsed quality scheme covering a wide range of trades. Neither guarantees a perfect project, but both demonstrate that the contractor has been independently assessed against recognised standards.
If your project requires electrical or gas work, ask whether the relevant trades are registered with recognised Competent Person Schemes such as NICEIC, NAPIT or Gas Safe Register. This allows certain work to be certified without separate inspection, helping projects progress more efficiently.
Speak to previous clients
Every contractor can provide glowing testimonials.
The more useful conversation is about how they dealt with problems.
Ask previous clients questions such as:
- What unexpected issues arose?
- How were they handled?
- Was the final account close to the original quotation?
- Was communication good throughout the project?
- Would you genuinely use them again?
- No building project is entirely without challenges.
A contractor’s response when something goes wrong often tells you more than a project where everything went perfectly.
Compare the detail, not just the price
Two quotations can differ significantly without either contractor being more expensive.
One builder may have included decorating, waste removal, Building Control fees and scaffolding, while another has excluded them entirely.
Before comparing prices, make sure each contractor is pricing the same specification.
Pay particular attention to:
- Provisional Sums
- Prime Cost allowances
- Exclusions
- Assumptions
- Who is responsible for supplying fixtures and finishes
Comparing like-for-like quotations almost always leads to better decisions than simply choosing the lowest figure.
Always have a written contract
A professional building project should always be supported by a written contract.
It should clearly define:
- The scope of works
- The contract sum
- Payment arrangements
- The construction programme
- How variations are agreed
- The procedure for resolving disputes
For many domestic projects, the JCT Home Owner Contract provides a clear and widely recognised framework that protects both homeowner and contractor.
Understand how payments will work
For most domestic projects, payments are usually best linked to clearly defined stages of completed work rather than fixed calendar dates. This helps ensure that payments broadly reflect progress on site.
Larger or more complex projects may instead use regular interim valuations prepared throughout the construction programme.
Whichever approach is adopted, both parties should understand exactly when payments become due and what they relate to.
Communication matters
Successful projects rely on good communication just as much as good workmanship.
Regular site meetings, prompt decisions and a clear written record of agreed changes help keep projects moving and reduce the likelihood of misunderstandings.
Most building disputes begin with assumptions rather than deliberate disagreements.
Trust your judgement
The period before work starts often tells you a great deal about how a contractor operates.
- Did they arrive when they said they would?
- Did the quotation arrive on time?
- Were your questions answered clearly?
- Did they explain potential problems as well as opportunities?
A contractor who occasionally tells you something you didn’t want to hear may simply be giving honest professional advice.
Finally, remember that you’ll be working closely together for several months. Professional competence is essential, but so is having confidence that you’ll enjoy working with the people you’ve invited into your home.
Warning signs
Be cautious if you encounter any of the following:
- A quotation with very little detail or no clear specification.
- No written contract.
- Pressure to make an immediate decision.
- Large upfront payments that significantly exceed the cost of securing a start date or ordering materials.
- Reluctance to provide insurance details or references.
- Requests for cash payments or suggestions that VAT can be avoided.
Questions worth asking every contractor
Before making your decision, consider asking:
- When did you last complete a project similar to mine?
- Can I visit a recently completed project?
- Who will manage my project on a daily basis?
- How many other projects will you be running at the same time?
- What items are allowances rather than fixed prices?
- How are variations costed and agreed?
- Who is responsible for Building Control and statutory approvals?
- How will you communicate progress throughout the build?
- What would make you decide not to take on this project?
