What is a workable day (werkbare werkdag)?
A workable day, in Dutch “werkbare werkdag”, is a working day on which normal work can be carried out on site. Dutch building contracts often express the construction period in workable days rather than calendar days. Days lost to bad weather or other circumstances outside the contractor’s responsibility then do not count.
How it works under the Dutch UAV 2012
The UAV 2012 (the standard Dutch administrative conditions for the execution of works) define a working day as a calendar day, except recognised rest days and public holidays, holiday days and other collective days off. Where a period is stated in workable days, paragraph 8 treats a day as unworkable if, through circumstances outside the contractor’s liability, most of the workers or machines could not work for at least five hours. For half a day the threshold is at least two hours.
In the UK and elsewhere, standard forms such as JCT or NEC deal with delay through extension-of-time or compensation-event clauses, with their own rules on weather. Always check which conditions your contract actually uses.
Worked example
A contract states 60 workable days. During the build there are public holidays, a two-week builders’ holiday and several days lost to frost and storms. The actual duration is then well over 12 calendar weeks. That is why a completion date in workable days is less predictable for a client than a fixed date.
Tips for clients
- Ask for a programme with calendar dates alongside the number of workable days.
- Have unworkable days recorded, for example weekly in a site diary, to avoid disputes later.
- Plan for winter: if the shell is built in winter, expect delays.
- Delay damages: a penalty for late completion only works if it is clear how the period is calculated.
Related terms
- Unworkable weather
- Building contract
- Site diary
- Specification
- Practical completion
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.