What is daywork in construction?

Daywork (often called dayworks) is a way of paying for extra work by the hour. Instead of being paid an agreed price for the job, the contractor is paid for the time the workers and machines spent on it and for the materials used. An agreed amount is then added on top to cover overheads and profit.^[1]

Most work on a site is paid at prices agreed in the contract, such as a price per metre of drainage or per cubic metre of concrete. Daywork is for work that doesn't fit those prices, which is usually extra or changed work that comes up on site. Because the contractor is paid for time rather than for what was built, the client will want proof of every hour.

When is work done on daywork?

Daywork is used when there is no sensible way to price the work from the rates in the contract. For example:

• Breaking out something unexpected in the ground, such as an old foundation.
• Putting right damage left by another contractor.
• Small changes that would cost more to measure than to do.

Daywork is for work you have been instructed to do, and arguments over whether work was properly instructed are common, especially when the programme is under pressure.^[1] Work done on a quick “just get it sorted” and only written up as daywork afterwards is the hardest to get paid for. So get the instruction before you start, and write down who gave it and when.

How daywork is priced

Your contract says which rules are used. You don't need to know the details, because your commercial team will do the pricing, but it helps to know the names they use.

• On building jobs, the rules usually come from a document published by RICS, the professional body for surveyors. It is called the Definition of Prime Cost of Daywork, and the current version has been in use since 2007. “Prime cost” simply means the actual cost of the labour, materials and machines. The contract then either adds a percentage on top, or uses hourly rates that already include everything.^[2][3] Machines are usually priced from a separate RICS list of plant rates.
• On civil engineering jobs, the rates usually come from the CECA Schedules of Dayworks. CECA is the trade body for civil engineering contractors. A new edition came out in August 2025. It has a separate section for rail, and most of its machine rates are given per hour.^[4][5]

Jobs on an NEC4 contract, which is common on large infrastructure projects, don't use daywork in the same way. Extra work is treated as a “compensation event”, which is NEC's name for a change that the client pays for. The price of the change is worked out from what the work actually cost the contractor.^[6] The CECA rates still turn up, though, because many NEC4 contracts use them to price the contractor's machines.^[5]

What is a daywork rate?

A daywork rate is the amount per hour that the contract allows for each type of worker or machine. For a worker, it starts from what that person really costs to employ. That includes their pay, the employer's National Insurance and their holiday pay, spread across the hours they work in a year. An agreed percentage is then added on top.^[7] The percentage is agreed when the contract is priced, so it is different on every job. Your contract will tell you what yours is.

The record that gets daywork paid

Daywork only gets paid if it can be checked, and the daywork sheet is how it gets checked. The sheet should say who worked, what their trade is and how many hours they did. It should list the machines used and how long each one ran, and the materials used with their delivery tickets. It should also describe exactly what the work was. Then it should be signed by the person who checks the work for the client.^[1]

That signature agrees that the facts on the sheet are right. It does not agree the price.^[8] Most building contracts also expect daywork sheets to be handed in soon after the work is done, often by the end of the following week, so check your contract for the exact deadline. A sheet that arrives a month late and just says “labour, 3 men” is the kind that gets refused.

If you're not sure who should sign, or what their signature means, see what a clerk of works signs.