Introduction
In contracting of work, the contractor undertakes to produce a work of a material nature, outside employment, for a price (Article 7:750 of the Dutch Civil Code, DCC). Most disputes arise not over the existence of the assignment, but over additional work, delivery, the price and liability for defects. The contract for work and the course of events during the work determine who bears what.
Formation, price and additional work
A contract for work is not subject to any form requirement and comes about even without a signature, as long as agreement is shown. Where no fixed price has been agreed, a reasonable price is due (Article 7:752 DCC). The contractor may charge for additional work only where they warned the client in time of the need for the resulting price increase, unless the client should have understood that need of their own accord (Article 7:755 DCC). The Supreme Court further defined that unless-clause in a dispute over additional work, in which the question was what degree of insight into the price increase is required on the client's part (Supreme Court 1 July 2022, ECLI:NL:HR:2022:989).
Duty to warn and delivery
The contractor must warn the client of inaccuracies in the assignment or defects in materials supplied by the client (Article 7:754 DCC). The work is delivered when the contractor indicates it is finished and the client accepts it; on delivery the risk passes and the maintenance period begins. Defects noted at delivery are recorded in a delivery file.
Liability after delivery and the Quality Assurance Act
For contracts for work concluded on or after 1 January 2024, the tightened regime of the Quality Assurance for Construction Act (Wet kwaliteitsborging voor het bouwen) applies. Whereas the contractor previously was in principle no longer answerable after delivery for defects the client ought to have discovered at delivery, the current Article 7:758(4) DCC provides that the contractor is liable for defects not discovered at delivery, unless those defects cannot be attributed to them. Whether the client could have discovered the defect is no longer decisive. This rule cannot be deviated from to the detriment of a consumer client, and a deviation for a business client must be expressly included in the contract itself; a mere reference to general terms does not suffice.
Termination and default
The client can terminate the contract at any time, but must then pay the price for the whole work, less the contractor's savings (Article 7:764 DCC). If the contractor does not deliver, or delivers defectively, rescission can follow after default and instalments paid can be reclaimed.
What decides the outcome
The outcome is determined by the contract for work, whether a warning was given in time and whether the additional work was agreed, and by the manner of delivery. A party claiming additional work must show agreement or the recognisable necessity; a party alleging defects must substantiate the delivery and the nature of the defect, with the date of the contract determining whether the stricter Wkb regime applies.