Day rate vs fixed price building work

Day rate building work pays for time: the builder charges for each day on site, and the final cost depends on how long the job takes. Fixed price work pays for an outcome: one agreed sum for a defined scope. The real difference between them isn't the price. It's who carries the risk.

On a day rate, you do. On a fixed price, the builder does. Everything else in this guide follows from that one sentence.

When does a day rate make sense?

Day rates make sense when the work genuinely can't be scoped in advance: exploratory jobs, repairs of unknown depth, and small odd jobs where writing a quote would take longer than the work itself.

Opening up a ceiling to trace a leak is the classic case. Nobody can price what nobody has seen, and a fair day rate is the honest way to pay for discovery.

The going rates are knowable, at least. Across the major trade platforms in 2026, general builder day rates in the UK run from around £150 to £400 per day, with hourly rates of £25 to £60 nationally and £60 to £100 in London and the South East [1]. Those figures are for a skilled builder. A labourer working alongside typically charges £100 to £150 a day, and London and South East rates generally sit 20 to 40% above the national average.

For a full trade-by-trade breakdown in the capital, our guide to London builder day rates covers what each trade typically charges and what the rate does and doesn't include.

What does a builder's day rate actually include?

A day rate buys one thing: that builder's labour for the day. It almost never includes materials, skip hire, scaffolding, plant hire or the specialist trades a job pulls in, like the electrician or the plasterer. Each of those lands on your bill separately.

This is the single most common source of day-rate disputes. A homeowner hears "£250 a day" and budgets £1,250 for the week; the builder meant £1,250 plus materials, plus the skip, plus the sparky's day and a half. Neither of them was lying. They just weren't pricing the same job.

Get the exclusions in writing before anyone starts. And ask about VAT: a builder with turnover over £90,000 must be VAT registered, which puts 20% on top of everything unless the rate you were quoted already includes it.

When does a fixed price make sense?

Fixed prices make sense for any project with a definable scope: a bathroom, a kitchen, an extension, a whole-house renovation. If the work can be specified, it can be priced, and a priced project is one you can actually budget for.

A fixed price does something psychological as well as financial.

It aligns everyone's incentives with finishing. The builder profits by working efficiently, not by being present, and you stop doing that quiet daily arithmetic where every tea break has a price tag on it.

Worth knowing: builders price risk into fixed quotes, typically somewhere around 10 to 15% on top of their expected costs, because they're absorbing the unknowns. That premium is real, and it's worth every penny on a big job. You're not paying more for the same work. You're paying someone else to own the downside.

Day rate vs fixed price: the risks of each

The day-rate risk is drift: no ceiling, no deadline pressure, and a labour bill that grows a day at a time. The fixed-price risk is rigidity: change your mind mid-project and each change gets priced, agreed and papered before it happens.

Worth saying plainly: a builder preferring a day rate for a large, definable project is a small warning sign in itself. It can be innocent. It's also exactly how open-ended jobs are born.

Why do some builders push for day rates on big jobs?

Builders push for day rates on big jobs when they can't or don't want to absorb pricing risk: the scope is vague, the property is unpredictable, or their quoting discipline isn't strong enough to commit to a number.

Sometimes that's rational caution about a genuinely unknowable building.

More often, the vagueness is the problem, not the property. A project without drawings, decisions or a written scope can't be fixed-priced by anyone, and the day rate becomes the default because nobody did the definition work.

There are honest middle grounds too, and it's worth knowing their names. A capped day rate sets an agreed ceiling the bill can't pass. A provisional sum inside a fixed quote ring-fences the genuinely unknown bit (say, £2,000 for whatever's under the floor) while everything else stays fixed. The third model you'll sometimes be offered is cost-plus: materials and labour at cost, plus an agreed percentage for the builder. It's transparent on paper, but it shares the day rate's core weakness, because nobody is on the hook for the total.

And if a job starts on a day rate because it had to, convert it once the unknowns are known. Two days of opening up, then a fixed quote for the repair. That sequence is completely normal, and good builders offer it without being asked.

How do you get a fixed price you can trust?

A trustworthy fixed price needs three ingredients: a locked design, a written scope of works, and an itemised quote against both. Give a builder certainty and they can give you a number that holds.

Design is the ingredient people skip.

Every unmade decision, from the tile to the tap to whether the wall moves, is a gap the price can escape through later. It's why Beams locks the design and specification before builders quote. Our interior design service is there to help you get there, as much or as little as you want, because a fully specified design is what makes a fixed price possible at all.

Then make sure the number you're given is the binding kind. Our guide to the difference between a quote and an estimate shows how to tell a commitment from an educated guess dressed up as one.

If you do run day-rate work, keep a site diary. One line a day: who was on site, what got done. It takes thirty seconds, and it's the difference between "it feels slow" and "we're four days over the estimate with the same wall half-built", which is a conversation you can actually have.

How does payment work on a fixed-price project?

Fixed price doesn't mean paid up front. On a well-run project the agreed sum is released in stages as work completes, which keeps the fixed price honest from both directions: the builder is paid promptly for finished stages, and you never have more money out than work done.

On Beams projects that means four milestones (20% at break ground, 30% at first fix, 20% at practical completion, 30% at sign-off), with funds sitting in your Beams account rather than the builder's until you approve each one. The mechanics are all in our guide to milestone construction payments.

Day rate or fixed price, that's the structure that keeps everyone comfortable: pay for what you can see.

Want to start from a fixed price rather than a running total? Get a free estimate and see what your project should cost before anyone starts.

Common questions about day rates and fixed prices

Is it cheaper to pay a day rate or a fixed price?
A day rate looks cheaper because it carries no risk premium, the 10 to 15% a builder adds to a fixed quote for absorbing the unknowns. It only stays cheaper if the job runs exactly to time. Run over, and you're paying the premium anyway, a day at a time, with no ceiling.

Do builders charge VAT on top of a day rate?
Only if they're VAT registered, which is compulsory once turnover passes £90,000. A registered builder adds 20%, so always ask whether a quoted rate includes it before comparing two builders' numbers.

Should you pay anything up front on day-rate work?
No. Day-rate work is normally invoiced weekly in arrears, and there's nothing to secure with a deposit. If money is requested before work starts, the rules in our guide to how much deposit to pay a builder apply just the same.

What is a cost-plus arrangement?
You pay the builder's actual costs plus an agreed margin, usually 15 to 25%. It suits genuinely unpredictable restoration work, but demand open-book receipts and a target budget, or it becomes a day rate with better paperwork.

Sources

[1] MyBuilder, Builder Day Rate guide (updated May 2026) – general builder day rates of £150–£400; UK hourly rates £25–£60, rising to £60–£100 in London and the South East. https://www.mybuilder.com/handyman/price-guides/builder-day-rate