What to Ask Your Builder Before You Sign

Membership shows commitment to standards and gives you an independent complaints route if things go sideways.

Ask for a copy of the certificate — you want minimum £2m cover for domestic work. Don't just take their word for it.

Legally required if they have employees. If someone gets injured on your property, you could be liable without it.

Especially important for gas, electrical, or structural work. Ask for Gas Safe, NICEIC, or relevant certificates.

If they're not VAT registered but quoting over £90k, that's a red flag. VAT status also affects your final price by 20%.

Awards from trade bodies, local council partnerships, or manufacturer accreditations all show they take the work seriously.

A fixed price means the builder absorbs cost overruns. An estimate can change — sometimes dramatically.

You should see separate lines for materials, labour, and any other costs. A single lump sum makes it impossible to compare quotes fairly.

Always confirm whether VAT is included. An unexpected 20% on top can blow your budget.

Materials, labour, skip hire, scaffolding, building control fees, decoration, cleaning — get every item listed so nothing falls through the cracks.

Never pay more than 10–15% upfront. Stage payments tied to completed milestones are standard and protect both sides.

Ask about potential extras — unforeseen structural issues, design changes, material price increases. Know what could push the price up before it happens.

Material prices fluctuate. Most quotes are valid for 30–60 days. If you're not ready to commit, check when you'd need a re-quote.

Get both start and completion dates in writing. A builder who can start tomorrow might not have enough work — that's worth questioning.

Some builders juggle multiple jobs. Clarify who will be your day-to-day contact and how often the main contractor visits.

Most residential builders work 8am–5pm weekdays. Confirm there won't be early starts or weekend noise without your agreement.

A skip on your drive, materials in the garden, vans blocking the road — plan for this so it doesn't cause problems with neighbours.

For major renovations, discuss temporary facilities. Knowing you'll be without a kitchen for three weeks helps you plan ahead.

Ask if there are penalties for late completion. At minimum, get agreement that they'll notify you promptly if delays occur.

A verbal agreement isn't worth the paper it's printed on. Insist on a written contract covering scope, price, timeline, and payment terms.

Most good builders offer 12 months to fix any defects after completion. Some trade body members offer longer guarantees — ask what's covered.

An insurance-backed guarantee (IBG) protects you even if the builder goes bust. It's the gold standard for peace of mind.

Check if the contract includes a dispute resolution process — mediation is cheaper and faster than court. Trade body membership often includes this.

Agree upfront how design changes are handled. Good contracts have a variation process — verbal changes lead to arguments about cost.

Life happens. Understand the cancellation terms and any costs involved before you sign, not after.

Look for projects similar to yours in size and scope. Before-and-after photos are especially useful.

Nothing beats seeing the work in the flesh. Pay attention to the finish quality — skirting joints, tiling edges, paint lines.

A quick phone call with someone who's been through the process is worth more than any brochure. Ask about communication, timekeeping, and snagging.

Look at Google, Checkatrade, MyBuilder, or Trustpilot. Pay attention to how they respond to negative reviews — that shows character.

Experience with your specific type of work matters. A loft conversion specialist might not be the best choice for a kitchen extension.

A tidy site is a safe site. End-of-day tidying and regular skip changes should be standard, not an extra.

For structural work, someone needs to arrange inspections. Clarify whether this is included or something you need to organise yourself.

Most projects involve electricians, plumbers, or plasterers. Confirm whether the main builder coordinates them or if you're left to arrange specialists separately.

Some builders manage the entire planning process; others expect you to have permission in place before they start. Know which camp yours falls into.

Agree on a single point of contact and a preferred method — WhatsApp, email, weekly site meetings. Good communication prevents most disputes.

Knowing the process upfront makes it easier to speak up. A weekly walk-through with the builder is a great way to catch issues early.