How to vet a builder or general contractor before you hire

Most building jobs that go wrong could have been spotted before the contract was signed. Vetting a builder is not about gut feeling. It is a short list of checks that any homeowner can do in an evening: confirm who the business is, confirm they are licensed or accredited where that applies, confirm they are insured, talk to past clients, and agree a payment schedule that never puts you far ahead of the work.

This guide covers the checks that apply everywhere, then the ones specific to the UK, the US, Canada and Australia.

Start with the basics: who are you actually hiring

Before you look at accreditations, make sure the business is real and traceable.

• A full name and a physical address. A mobile number and a first name is not enough. You need somewhere to send a letter if something goes wrong.
• The legal entity. Is it a sole trader, a partnership or a limited company (an LLC or corporation in the US)? In the UK you can look up a limited company on Companies House and see its directors and filing history. A company that was set up very recently, or whose directors have a string of dissolved companies behind them, deserves more questions.
• How long they have traded under this name. A newer business is not automatically a problem, but you want to know.
• Who will be on site. Ask whether the person quoting will run the job, and which parts will go to subcontractors.

Checks in the UK

There is no single licence for builders in the UK, so the work falls on you to check memberships and paperwork.

• TrustMark. TrustMark is the government-endorsed quality scheme for work in and around the home. Registered businesses have been checked by a scheme operator. Search the TrustMark register by business name rather than trusting a logo on a van or website.
• Federation of Master Builders (FMB). The FMB is a trade association for builders. Members are vetted when they join. Confirm membership through the FMB's own directory.
• Building Control. Many jobs, such as extensions, structural alterations, loft conversions and some re-roofs, need Building Regulations approval. That comes either from your local authority Building Control team or from a registered private building control body. Ask the builder who will handle the application and inspections, and make sure you receive a completion certificate at the end. You will need it when you sell. Planning permission is a separate matter from Building Regulations, so check both.
• Competent person schemes. For some work, such as electrics, gas, windows and heating, a registered tradesperson can self-certify that the work meets the regulations. Gas work must be done by someone on the Gas Safe Register. If the builder subcontracts these trades, ask for the names and check them yourself.
• Public liability insurance. Ask for the certificate and look at the insurer, the policy holder name and the expiry date. If they employ staff, they should also hold employers' liability insurance.

Checks in the US

• State contractor licence lookup. Most states run an online lookup through a contractor licensing board or a consumer protection department. Some states license general contractors at state level, some leave it to cities or counties, and some only license specific trades. Search the licence number yourself, check that the name matches the business you are dealing with, that it is active, and whether there are complaints or disciplinary actions.
• General liability insurance and workers' compensation. Ask for a certificate of insurance. A good contractor will have their insurer send it to you directly. Workers' comp rules vary by state, but if an uninsured worker is injured on your property, you may end up dealing with the consequences.
• Bonding. Some states and cities require contractors to carry a bond. It is worth asking about, but a bond is not the same as insurance.
• Permits. Structural, electrical, plumbing and many roofing jobs need a permit from the local building department. The contractor should pull the permit in their own name and book the inspections. See contractor red flags for why a contractor asking you to get the permit is a warning sign.
• Lien waivers. In the US, subcontractors and suppliers who are not paid by your contractor may be able to put a lien on your property. Ask for lien waivers as payments are made, especially on larger jobs.

Checks in Canada and Australia

In both countries, licensing is set by the province, territory or state, and the rules differ a lot from one place to the next. Do not rely on what applies elsewhere. Go to the regulator for the area where the work is being done.

• Canada. Some provinces license contractors directly. In Quebec, for example, contractors need a licence from the Régie du bâtiment du Québec. Elsewhere, licensing may apply only to new home builders or be handled by the municipality. Trades such as electrical, gas and plumbing are regulated separately. Check with your province and your city's building department, and ask about permits.
• Australia. Builders and tradies doing residential work above a certain size generally need a licence from the state or territory regulator, such as the QBCC in Queensland, or the NSW Government licence check in New South Wales. Use the regulator's online licence check, confirm the licence class covers the work, and ask about home building warranty insurance, which several states require for larger residential jobs.

References and past jobs

Online reviews help, but they are easy to fake and easy to curate. Ask for references from clients whose jobs were similar to yours and finished in the last year or so, and actually call them.

If you can, visit a past job, or a current one. Seeing a live site tells you a lot: how materials are stored, whether the crew seems organised, and whether the person in charge is actually there. A builder with a good record is usually happy to arrange this.

Get it in writing

A proper written quote or contract should cover the scope of work, materials and who supplies them, start and finish dates, the payment schedule, how changes are priced and approved, who gets permits and sign-off, clean-up and waste removal, and any guarantee on the workmanship. Our guide to getting quotes explains how to compare these line by line.

A payment schedule that protects you

The safest arrangement is one where you pay for work that has been done, not work that has been promised.

• Keep any deposit modest and tied to something concrete, such as materials ordered specifically for your job. Some US states and Australian states limit how much can be taken as a deposit for home building work, so check locally.
• Link stage payments to stages you can see: foundations in, roof on, first fix complete, Building Control or permit inspection passed.
• Hold back a final payment until the snagging list is finished and you have the completion certificate or final inspection.
• Pay by bank transfer or card to the business name on the contract, and keep records. Avoid large cash payments.

Quick vetting checklist