How to Choose a Builder in London: 7 Things to Check

A great builder will keep your project on time, on budget and stress-free. The wrong one can cost you thousands and months of your life. The good news is that most problems are avoidable if you carry out a few simple checks before any money changes hands.

1. Proof of insurance

Ask to see the builder’s public liability insurance, and confirm it is current. This protects your property and anyone on site if something goes wrong. Any established builder will be happy to share a certificate. If they hesitate, treat it as a warning sign.

2. Recent, relevant work

Ask to see projects similar to yours, ideally from the last year or two. Photos are a start, but references you can actually speak to are better. A good question to ask a past client is whether the final price matched the quote, and how the builder handled any surprises.

3. A detailed written quote

A verbal estimate is not a quote. Insist on an itemised, written, fixed-price quote that sets out materials, labour, timescales and what is excluded. This is the only way to compare builders fairly, and it protects you from vague pricing that creeps up once work begins.

4. A clear contract and payment schedule

Every project should have a written contract and a staged payment schedule tied to work completed. Be cautious of anyone asking for a large deposit upfront. Payments should reflect progress on site, not sit ahead of it.

5. Accreditations and memberships

Trade memberships and accreditations are a useful signal that a builder works to recognised standards. They are not a guarantee on their own, but combined with insurance and references they help you build a fuller picture of who you are hiring.

6. Communication and a single point of contact

Notice how a builder communicates before you hire them. Do they reply promptly, explain things clearly and turn up when they say they will? On the project itself, one dedicated point of contact who manages the trades on your behalf makes the whole experience far smoother.

7. Local knowledge and planning experience

In London, local knowledge matters. A builder who regularly works in your area will understand the housing stock, the parking and access realities, and the planning rules that apply, including conservation areas and permitted development. That experience helps avoid costly mistakes and keeps your project moving.

A quick final check

Before you commit, make sure you have seen proof of insurance, spoken to a recent client, and received a detailed written quote and contract. If a builder ticks those three boxes and communicates well, you are already in good hands.