James Whitaker
Why an hour of checking saves months of grief
Most homeowners pick a roofer, electrician or builder on the strength of a friendly phone manner and a keen quote. That is entirely understandable — but it is also how people end up with a leaking valley, an unfinished extension, or a certificate they cannot produce when they come to sell. The checks that separate a dependable tradesperson from a risky one take about an hour, cost nothing, and can almost all be done before you hand over a penny.
None of it is about being suspicious. It is about treating a £6,000 re-roof or a £40,000 renovation with the same care you would give to any other significant purchase.
Ask for recent examples, not a photo album from 2015
When you request references, be specific. A vague "we've done loads round here" tells you nothing useful. A better ask sounds like this: "Could you give me two or three customers from the last year whose job was similar to mine, ideally in this area?"
- Recent — within the last 12 to 18 months. Working practices, staff and standards change.
- Relevant — a full slate re-roof if that is your job, not a gutter clearance. A consumer unit replacement if you need electrical work.
- Local and visitable — a street address you can drive past from the road, so you can judge the finished work yourself.
Then actually ring the people on the list. Ask how accurate the quote turned out to be, whether the team turned up when they said they would, how snags were handled, and whether the site was left tidy each evening. The most revealing question is simple: "Would you use them again?" If a tradesperson cannot supply two or three recent references, that in itself is an answer.
Check public liability insurance — and check it properly
Public liability cover pays out if a tradesperson damages your property or injures someone while working on it — a slipped tile through a conservatory roof, a dropped hammer on a car bonnet. For domestic work, £2 million is a sensible floor and many policies offer £5 million or more. Ask for a copy of the certificate before work starts, not after.
Three things to verify:
- The certificate is current. Look at the expiry date, and be wary of a document that lapsed months ago.
- The policyholder matches the business you are hiring. If the certificate is in the name of a dissolved company or an unrelated individual, it will not protect you.
- The cover suits the job. Some policies exclude hot works such as torch-on felt, or work above a certain height — both very relevant on a roof.
If they employ anyone at all, including a labourer or an apprentice, they are legally required to hold employers' liability insurance of at least £5 million. Do not take "we're all self-employed" at face value. The certificate carries the insurer's or broker's details, so a two-minute phone call will confirm the policy is live and in force. That call is worth making.
Qualifications and registration: what is actually required
Requirements differ by trade, and knowing them keeps you on solid ground.
- Electricians in England and Wales should be registered with a competent person scheme so they can self-certify notifiable work under Part P of the Building Regulations. Ask for their registration number and verify it on the scheme's own register.
- Gas work must be carried out by a Gas Safe registered engineer. Check the photo card and confirm the registration on the official register.
- Roofing has no statutory licensing in the UK, so look for manufacturer-approved installer status for the system being fitted, evidence of working-at-height training, and CSCS cards for anyone on site.
- General builders also hold no licence. Check the company is active at Companies House, confirm any VAT number they quote, and ask whether they use subcontractors — and if so, how those trades are vetted.
Written quotes, deposits and payment stages
A verbal estimate is not enough for anything substantial. Ask for a written quote that sets out the scope of work, materials and brands, the timescale, the start date, and what is excluded. For larger projects, a written contract is worth the small amount of effort it takes.
On money, keep it structured. A deposit covering materials is reasonable; a request for half the job up front in cash is not. Tie stage payments to completed milestones, keep a retention of around 5 per cent on bigger jobs until snagging is finished, and never settle the final balance before you have walked the job through and are satisfied. A proper paper trail also protects you if a dispute arises later.
Red flags worth walking away from
- Reluctance to provide an insurance certificate, a business address or a reference.
- Cash-only discounts and pressure to decide on the spot.
- Requests to pay into a personal account when you are dealing with a limited company.
- Quotes given as a day rate with no defined scope or end point.
- No landline, no fixed address, no trace at Companies House.
A genuinely good tradesperson expects these questions and will answer them cheerfully. The best roofers, electricians and builders in your area are busy precisely because they do things properly. If asking for a certificate or a reference makes someone prickly, that is useful information — and it has arrived before you have paid them anything.
