How to find a good builder in London

Finding a good builder in London means sourcing names through architects, engineers or a vetted platform, checking three insurances and the borough rules that apply, then pricing three builders against one written scope.

Seven checks, in the order you need them:

1. Use the right sources. Architects, structural engineers, neighbours who have done the same job and vetted platforms all beat a cold directory search.
2. Learn the London rules. Party wall notices, conservation areas, Article 4 directions and your borough's building control all change how the job runs.
3. Read all three insurance certificates. Public liability, employer's liability and contract works cover.
4. Verify the company and see the work. Companies House filing history, plus two references from projects like yours and one site you can walk round.
5. Ask how they actually run a site. Who is on site daily, what gets subcontracted, how variations are priced, who deals with the council.
6. Price against London, not the UK average. Three quotes against one scope, sense-checked against local day rates.
7. Put it in writing before anyone starts. Contract, staged milestone payments, retention held back until snagging is signed off.

Where do you find builders in London?

Builders in London come from five main sources: architects and structural engineers, personal recommendations, trade directories and review sites, professional bodies such as the Federation of Master Builders, and vetted-builder platforms that check credentials before introducing anyone.

Each route carries a different level of assurance.

• Architects and structural engineers are the most underrated route in London, because they watch contractors work at close range on every project they run. They know who reads a drawing properly and who improvises, and they have no reason to put forward anyone who will make their own design look bad. If you have already appointed a designer or engineer for a side return, loft or basement, ask them before you ask the internet.
• Personal recommendations are strong evidence, provided the project was similar to yours and on a similar street. A builder who fitted your neighbour's bathroom beautifully may not be the right lead on a structural job with a party wall and a planning condition attached.
• Directories and review sites cast a wide net but do little verification. Checkatrade, MyBuilder, Rated People and TrustATrader will hand you names within the hour. A profile tells you nothing about who actually turns up on site, or whether they have ever worked in your borough.
• The Federation of Master Builders and TrustMark inspect against membership criteria, which raises the floor and filters out the bottom of the market. Neither matches a builder to your particular project.
• Vetted-builder platforms do the verification for you. At Beams, every builder is vetted in person, with references checked and recent London work inspected before joining the network, and averages 15 years of residential experience. You can see the builders themselves before you ever meet one.

Whichever route you use, the checks below are still your job, or your platform's, before a contract gets signed. If you would rather start from a shortlist, we have already compared the best renovation companies in London.

What's different about hiring a builder in London?

Four things change in London. Most homes share a wall, so the Party Wall Act 1996 applies to a lot of ordinary work. Planning is tighter, because of conservation areas and Article 4 directions. Building control is run borough by borough across 32 boroughs plus the City of London. And access, parking and permitted working hours are all restricted in a way they are not on a detached house with a driveway. Our wider guide to the London specifics goes through each of them in more detail.

Party wall notices and party wall surveyors

If your work affects a wall or structure you share with a neighbour, the Party Wall Act 1996 applies and notice has to be served before anything starts. In terraced and semi-detached London housing that catches most of what people actually do: cutting into the party wall for steel beams on a side return, taking out a chimney breast, underpinning for a basement, or building a dormer off the shared wall. Excavating within three metres of a neighbour's foundations counts too.

Notice periods are two months for work to the party wall itself and one month for excavation. Your neighbour has 14 days to consent in writing, and silence counts as dissent, which means appointing a party wall surveyor to produce an award. Budget somewhere around £1,000 to £2,000 per neighbour, more on a basement, and add six to eight weeks to the programme. On a terrace with neighbours either side, that is two sets of notices.

A builder who never raises party walls when quoting a terraced house has told you something about their experience. Ask who serves the notices and who commissions the schedule of condition. It is usually you or your architect rather than the builder, and it needs doing early, because the award can gate your start date.

Conservation areas, Article 4 directions and listed buildings

Large parts of inner London sit in conservation areas, and boroughs use Article 4 directions to strip out permitted development rights that would apply elsewhere. In stretches of Islington, Camden, Hackney and Haringey you need planning permission for work that is permitted development in most of the country: replacing front windows, rendering a front elevation, paving a front garden, or adding a rear dormer.

Listed buildings are stricter again. Listed building consent covers the inside as well as the outside, so stripping plaster, moving a partition or replacing a staircase can all need consent, and doing it without consent is a criminal offence rather than a planning argument.

So ask each builder on your shortlist for a project in the same borough, ideally on a similar street. Someone who has already worked through a Camden or Kensington and Chelsea planning condition, with a conservation officer looking at window details, will handle yours faster than someone learning it on your house.

Building control varies borough by borough

The building regulations are national. How they get administered is not. Each of the 32 London boroughs plus the City of London runs its own building control team, with its own fee scale, lead times and inspection habits, and you can use a private registered building control approver instead.

The practical difference is timing. Some boroughs turn a full plans application round in a few weeks, others take considerably longer, and inspectors book up in the summer. Agree in writing who submits the application, who books each inspection and who collects the completion certificate. Structural work signed off late is one of the most common reasons a London completion date slips, and it also holds up a sale later.

Access, skips, parking and working hours

On a terraced street in Wandsworth or Walthamstow there is nowhere to put a skip, a mixer or a van.

That costs money before anyone lifts a tool. A borough skip permit runs roughly £30 to £80 a week and needs renewing. Parking bay suspensions or controlled parking zone dispensations for a contractor's van are charged per bay per day, and in inner London they can add a few hundred pounds a month across a project. Boroughs also restrict noisy work, typically to about 8am to 6pm on weekdays and 8am to 1pm on Saturdays with nothing on Sundays or bank holidays, and they will act on a neighbour's complaint.

Narrow access changes method as well as cost. With no side gate, every bag of sand goes in through the hallway and every bag of spoil comes back out the same way. A rear extension can need a hand-dig where a mini digger would be used elsewhere, or a crane lift over the roof. Ask each builder how they plan to get materials in and waste out of your specific house. The ones who have worked your kind of street answer immediately, with numbers.

What insurance should a builder have?

A builder working on your home should hold three policies: public liability insurance, employer's liability insurance if they employ anyone, and contract works or all-risk cover for the works in progress. Ask for all three certificates and check the dates.

• Public liability. Covers damage to your property and injury to third parties. £2 million is a sensible minimum on residential work and £5 million is common on structural jobs, which matters more in a terrace where the third party is the family the other side of the wall.
• Employer's liability. Legally required at £5 million minimum for any builder with employees. A genuine sole trader with no staff is exempt, so its absence is not automatically a problem, but a firm sending four people to your house needs it.
• Contract works, sometimes sold as all-risk cover. Insures the work in progress: a half-built extension hit by fire, flood, storm or theft of materials. Public liability will not pay, because nobody was negligent, and your own buildings policy usually excludes it. Without this one, somebody pays to build the same wall twice.

Get the certificates emailed to you rather than photographed on site, and check the policy is live on the date work starts rather than the date you asked. Tell your own insurer what you are doing as well, because most home policies restrict or void cover during structural work that has not been declared.

How do you check a builder's company and past work?

Look the company up on Companies House, speak to two or three past clients with projects like yours, walk round one finished or live site, and confirm Gas Safe registration for gas work and a Part P qualified electrician for notifiable electrics, whether in-house or subcontracted.

Companies House is the quickest check and the one most people skip. A run of dissolved companies with the same directors behind a freshly incorporated one is how builders shed liabilities and warranties and start again. The filing history also shows how long the trading entity has really existed, which is often a lot shorter than the number of years quoted on the website.

References are worth far more when you ask what went wrong rather than what went right. Every project hits a problem. You are listening for how it got handled, how fast, and who paid.

Then see a site. A live site tells you about organisation, dust protection and whether the same faces turn up each morning. A finished one tells you how the work looks two years on. Our guide to vetting a builder takes each check in forensic detail, including exactly what to ask for in writing and what a bad answer sounds like.

What should you ask a builder before hiring them?

The questions that reveal the most cover availability, who is on site, subcontracting, payment terms, how variations get priced, who handles the borough and the party wall, and what warranty backs the work.

Ask these at the first site visit:

• Who will be on site day to day, and how many other projects run alongside mine?
• Which trades are in-house and which are subcontracted?
• How do you price changes once work has started?
• What payment schedule do you propose, and what deposit do you ask for?
• Who submits the building control application to the borough, and who serves the party wall notices?
• Where will materials and waste go, and who arranges the skip permit and any parking suspension?
• What warranty do you offer on workmanship, and is it written down?
• What is your realistic start date and duration, and what would move either?

A good builder answers all of these comfortably, because a good builder has been asked them a hundred times. The full list, grouped by what each answer actually tells you, is in our 20 questions to ask a builder.

What should a London builder cost, and how many quotes do you need?

Expect a London builder's day rate of roughly £300 to £450, against a UK average of about £200 to £350, and expect a London project to land somewhere between 15% and 30% above published national figures for the same scope. Get three quotes, all priced against the same written scope of works.

The premium is not mystery money. Skilled labour is scarcer here and paid accordingly, permits and parking are billed weekly, waste disposal costs more, restricted access slows every delivery, and the better firms are booked months out so they price from a position of strength. Our breakdown of what builders charge per day in London gives rates trade by trade, so you can read a quote line by line instead of reacting to the total.

The scope of works is what makes three quotes comparable. Three builders pricing their own assumptions produce three different projects at three different prices, and the cheapest usually assumed the least. Three builders pricing one specified scope produce numbers you can actually set side by side. It is why Beams writes a detailed scope first, then introduces up to three vetted builders to quote against it. Our guide to comparing multiple quotes walks through the process end to end.

Treat a quote dramatically below the other two as a warning rather than a bargain. In London the missing money tends to reappear as variations once the floor is up and the wall is open.

How should you pay a builder, and what should be in writing?

Pay in staged milestone payments tied to completed work, with a deposit of 5% to 10% for materials rather than a large sum in advance. Before anyone starts, get a written contract covering scope, price, payment schedule, start and completion dates, how variations are priced, and a workmanship warranty.

Milestone payments line everyone's incentives up. The builder gets paid promptly for finished stages, and you never have more money at risk than the work you can stand and look at. The safest version holds the funds with a third party and releases them only when you sign off a stage, which is how payments run on a Beams project. Hold a final 5% to 10% back until snagging is done.

The contract itself does not need to be exotic. For most residential projects a JCT Home Owner contract or JCT Minor Works covers the ground properly, and a builder's own written contract can be fine if the scope, price, dates, variation mechanism and default position are all in it. Every Beams project includes the contract and milestone structure as standard, plus a 12-month workmanship warranty from the builder, and if that builder leaves the network or stops trading inside those 12 months, Beams steps in with up to £10,000 of cover.

A cash discount for skipping the paperwork costs more than it saves. No paper trail means no contract, no warranty and no recourse. And if a builder resists putting things in writing at all, they have answered your most important question early, for free.

How Beams finds you a good builder

Doing all of this properly takes weeks: gathering names, chasing references, reading certificates, writing a scope, then comparing quotes that were never comparable to begin with. That is the work a managed home renovation takes off you, and removing it is what Beams was built for.

Every builder in the network has already been through it. We interview them in person, check insurance, references and the Companies House record, and inspect recent London work before they can join. Insurance is re-verified at every renewal and performance is tracked on every project afterwards, so vetting is a standard they keep rather than a badge they earned once. Because the work is all in London, they arrive already knowing how their borough's building control behaves and what a party wall award does to a programme.

So by the time you meet a Beams builder, the hard checks are finished. Get a free estimate and you will meet up to three personally vetted London builders pricing one proper scope, with contracts, secure milestone payments and a warranty already in place.

Frequently asked questions

How much deposit is normal for a London builder?
Five to ten per cent of the contract value, and normally for materials the builder has to order rather than for their time. On a £60,000 side return and kitchen that is £3,000 to £6,000. Anything at 25% or more before work starts, or any request for money before a contract is signed, is a reason to stop. Staged payments against completed work protect you far better than a large sum sitting with someone you met a fortnight ago.

Do I need a party wall agreement?
If the work affects a wall or structure you share with a neighbour, yes. Cutting into the party wall for beams, removing a chimney breast, underpinning, and excavating within three metres of a neighbour's foundations all trigger the Party Wall Act 1996. Serve notice two months ahead for work to the wall itself and one month for excavation. If your neighbour does not consent in writing within 14 days that counts as dissent, and a party wall surveyor prepares an award. A rear extension that keeps clear of the shared wall and the neighbour's foundations may not need one, but check before you dig.

Is Checkatrade or the FMB better?
They do different jobs. Checkatrade is a directory with reviews and a light set of checks, so it gives you volume and public feedback fast. The Federation of Master Builders inspects a sample of a member's work and requires firms to have been trading for a minimum period, so it is a much shorter list with a higher floor. FMB membership is the stronger signal, Checkatrade gives you more names to work through. Neither removes the need to read the insurance certificates and the Companies House record yourself.

How far ahead should I book a builder in London?
Three to six months for a good London firm on an extension or whole-house project, and longer for a specific builder or a spring start. Smaller jobs move quicker, often four to eight weeks. Add the approvals in front of that: a householder planning application takes around eight weeks from validation, and a party wall award can take another six to eight. A builder who can start on your London terrace next week is usually a builder who has just lost a job.

Should a quote include VAT?
It should state the position clearly either way. A VAT-registered builder has to show VAT at 20%, and a quote that leaves it ambiguous is a £10,000 surprise on a £50,000 job. Firms under the VAT registration threshold do not charge it, which is part of why a smaller outfit can look cheaper for identical work. Some projects qualify for a reduced or zero rate, including conversions that change the number of dwellings and properties empty for more than two years, so ask which rate applies to yours rather than assuming 20%.

Where this guidance comes from

The checks, deposit norms, insurance levels and contract standards here reflect independent UK consumer and industry guidance rather than Beams' commercial terms: the Federation of Master Builders, TrustMark, the HomeOwners Alliance, Citizens Advice on consumer rights for building work, and the JCT contract family. The party wall and planning points follow the government's Party Wall Act 1996 explanatory booklet and the Planning Portal. London day rates and project premiums reflect Beams' own quoting data across London boroughs alongside published national cost guides.

Sources

1. GOV.UK, Party Wall Act 1996 guidance for homeowners: https://www.gov.uk/party-walls-building-works
2. Planning Portal, conservation areas, Article 4 directions and listed buildings: https://www.planningportal.co.uk
3. Federation of Master Builders, hiring a builder guidance: https://www.fmb.org.uk
4. TrustMark, government-endorsed quality scheme: https://www.trustmark.org.uk
5. HomeOwners Alliance, builder and quote guidance: https://hoa.org.uk
6. Citizens Advice, problems with building work and consumer rights: https://www.citizensadvice.org.uk
7. JCT, Home Owner and Minor Works contract family: https://www.jctltd.co.uk