What is daywork in construction?

Daywork is a method of valuing extra or varied work that cannot be properly measured or valued using contract rates. Work is charged at cost (prime cost) plus agreed percentage additions to cover overheads and profit. It is typically agreed in the contract as a fallback for unmeasurable variations.

What are the RICS daywork percentages?

The RICS Definition of Prime Cost of Daywork suggests percentage additions to cover overheads and profit. Typical additions are: Labour 130-160% (covering NI, holiday pay, supervision, overheads, profit), Materials 10-20%, and Plant 5-15%. These are starting points for negotiation.

When should daywork be used?

Daywork should only be used when work cannot be valued by measurement - typically unforeseen problems, complex variations, or emergency work. It should be agreed in advance and daywork sheets signed daily by the client representative.

What should be on a daywork sheet?

A daywork sheet must record: date, description of work, operatives names and hours, materials used with costs, plant/equipment used with hire rates. It should be signed by both the contractor and the client/architect representative, ideally on the same day.

How do overtime rates work in daywork?

Overtime is typically charged at 1.5x (time and a half) for weekday overtime and 2x (double time) for weekends and bank holidays. The percentage addition is then applied on top. Always confirm overtime rates in the contract before undertaking the work.

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Daywork Rate Calculator

Calculate daywork charges using RICS percentage additions

Labour Hours

Hourly Rate

Trade Category

Materials at Cost

Plant Hire Cost

How We Calculate This

Enter the base labour hours and hourly rate, materials cost at invoice value, and plant hire cost. The calculator applies RICS-style percentage additions to each element: labour percentage covers NI, holidays, supervision, overheads, and profit; materials percentage covers handling, waste, and profit; plant percentage covers transport, maintenance, and profit. The total daywork charge is the sum of all elements with their additions.

Frequently Asked Questions

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Last updated: March 2026

All calculations are estimates. Verify with your supplier.