How to Choose a Builder: Questions to Ask Before You Hire

Hiring the wrong builder can cost you thousands of pounds—not just in money, but in stress, delays, and inferior workmanship that takes years to put right. A botched kitchen extension, structural damage, or unfinished project leaves you worse off than if you'd spent time getting the decision right first.

The good news is that hiring a builder doesn't have to be a gamble. By knowing what to look for, asking the right questions, and checking credentials thoroughly, you can dramatically reduce the risk of a nightmare experience. This guide walks you through exactly what to do before you sign anything.

Qualifications and Accreditations That Matter

When a builder claims to be qualified, don't just nod and move on. Ask to see proof. Here are the UK bodies and credentials worth looking for:

• NHBC Registered: The National House Building Council provides warranty cover and guarantees structural integrity. This is particularly important if you're having building work done that affects the structure of your home.
• FENSA Registered: If electrical work, heating systems, or windows are involved, FENSA registration ensures the work meets Building Regulations. This matters because non-compliant work can affect insurance claims and resale value.
• Gas Safe Registered: Essential if gas work is involved. Unregistered gas work is illegal and dangerous.
• CSCS Card (Construction Skills Certification Scheme): Shows the builder has been assessed for competence in their trade.
• NVQ or City & Guilds Qualifications: These demonstrate formal training in specific trades—carpentry, plumbing, brickwork, and so on.
• Professional Body Membership: Bodies like the Federation of Master Builders (FMB) or the Institute of Carpenters have membership standards and dispute resolution processes. Membership isn't foolproof, but it adds accountability.
• Public Liability Insurance: This protects you if someone is injured on your property or your neighbour's property is damaged. Always ask for proof of current cover.

Don't accept photocopies or promises to "send it over later." Ask to see the originals or verify credentials directly with the relevant body online.

8 Essential Questions to Ask Every Builder

1. Can you provide references from three recent jobs of a similar size?

Recent references are much more useful than work done five years ago. Ask specifically for jobs completed in the last 12 months. Contact those clients and ask about timeliness, communication, cleanliness, and whether they'd hire the builder again. A builder confident in their work will have happy clients ready to speak up.

2. What's included in your quote, and what isn't?

Vague quotes are a common source of conflict. Push for specifics: materials, labour, scaffolding, waste removal, and VAT. Ask what happens if the work uncovers unexpected problems—dry rot, dodgy wiring, structural issues. Will the cost escalate, and if so, do they need your approval first?

3. How long will the work take, and what happens if you run late?

Get a start date and finish date in writing. Ask what could delay the project and whether there are penalties for overrunning. Some builders blame weather or unexpected issues; fair enough. But they should have realistic timescales and a communication plan if delays happen.

4. What's your payment schedule?

Never pay the full amount upfront. A reasonable schedule is 25% deposit, 50% halfway through, and 25% on completion. Ask what triggers each payment—for instance, payment at 50% should only happen once certain milestones are met, not just because they've spent half the time on site.

5. Do you have public liability and employer's liability insurance?

Ask to see the certificate. Check it's current and covers the value of your project. If they can't prove it, walk away. You're liable if someone is injured on your property and the builder isn't insured.

6. Who will do the work—you directly, or subcontractors?

Some builders manage teams, others work alone. Either can be fine, but you need to know who's actually doing the work. If they use subcontractors, ask whether those subs are insured and whether the main builder is responsible if something goes wrong.

7. What's your experience with Building Regulations approval?

If your project needs Building Control approval—extensions, structural work, electrical upgrades—the builder should be familiar with the process. Ask whether they'll liaise with the inspector or if that's your job. Clarify who pays for inspection fees.

8. Can you provide a written contract?

Never rely on a handshake or a text message. A proper contract should outline the scope of work, timeline, payment terms, insurance details, and what happens if something goes wrong. If they refuse a contract, that's a red flag.

9. What's your cancellation and complaints policy?

Ask what happens if you need to stop the work, and how disputes will be resolved. If they're a member of a professional body, that body often has a complaints procedure you can use if things go south.

10. Will you clean up after yourselves daily?

This sounds small, but it reflects professionalism. A builder who leaves the site tidy each day, maintains the site safely, and minimises disruption to neighbours is someone who takes their work seriously.

What Good Reviews Look Like—and What Don't

Reviews are useful, but they're not the whole story. Good reviews tend to be specific: "They finished on time, communicated well when a problem came up, and the quality is excellent." Fake reviews are vague and gushing: "Brilliant work, highly recommend!" with no detail.

Watch out for clusters of five-star reviews posted close together, or reviews that read like marketing copy. Check when the reviews were posted—a builder with one glowing review from three years ago and nothing recent might not be active anymore.

Trust reviews that mention problems and how the builder handled them. If a client says, "We found asbestos, and they dealt with it professionally and transparently," that's more credible than someone who claims everything was perfect.

Red Flags to Walk Away

• Unwilling to provide references or insurance proof
• Pressure to pay a large deposit (more than 25%) upfront
• Vague or verbal quotes with no written breakdown
• No mention of Building Regulations or Planning Permission
• Reluctant to discuss the contract in detail
• Unregistered for FENSA or Gas Safe work they claim to do
• No public liability insurance
• Poor communication—slow to respond to emails or calls
• Bad-mouthing previous clients or competitors excessively
• Offering a significantly lower quote with no explanation of why

Comparing Quotes Fairly

Never hire on price alone. Get three quotes, but don't automatically choose the cheapest. A quote that's half the price of others usually means something is being cut—cheaper materials, less detailed work, or hidden costs later.

Compare quotes line by line: do they include the same materials, timescale, and scope? If one quote is £5,000 cheaper, ask why. Is it because they're using budget-grade fixtures, or because they're more efficient? Both answers are valid, but you need to know what you're getting.

Beware of quotes that are too detailed or vague. A good quote is clear, realistic, and explains any assumptions—for instance, "Assumes concrete floor is sound; if concrete removal is needed, additional cost will apply."

Find the Right Builder for Your Project

Choosing a builder takes time, but it's time well spent. By asking the right questions, verifying credentials, and checking references, you're stacking the odds in your favour.

Ready to start your search? Browse qualified, vetted builders on buildersmerchantsdirect.co.uk, the specialist UK directory where you can find local builders with proven credentials and genuine customer reviews. Get the help you need to make a confident choice.