Heidelberg Materials Workers Resume Work After Strike Deal

Workers at Heidelberg Materials concrete plants in Genk, Lommel, and Tessenderlo will return to work on Tuesday after a spontaneous strike on Monday morning ended with a negotiated agreement between unions and management. The work stoppage was triggered by the dismissal of a truck driver who was seriously injured in an accident after reportedly working a series of 15-hour days.

Background: A Serious Accident and a Dismissal

The dispute centers on an incident that occurred before Belgium’s construction holiday (bouwverlof). According to VRT NWS, an employee fell asleep behind the wheel of his truck after a long series of 15-hour working days. The truck tipped over and the man was seriously injured. Management subsequently dismissed him for what the union describes as “urgent cause” because he was not wearing his seatbelt at the time of the accident.

“Before the construction holiday, an employee fell asleep behind the wheel of his truck, after a long series of 15-hour working days,” said Jan Staal, secretary of the ABVV Bouw socialist construction union. “The man tipped over and was seriously injured. Then management dismissed him for urgent cause, because he wasn’t wearing his seatbelt.”

The company disputes key elements of this account. Vincent Allaerts, spokesperson for Heidelberg Materials, stated that “the dismissal did not happen for compelling reasons, and the claim that the employee fell asleep has not been established.” He emphasized that essential safety rules were not followed, including the failure to wear a seatbelt during the accident, and that “safety is always the top priority at Heidelberg Materials.”

The Spontaneous Strike and Negotiations

Workers at the three Limburg locations spontaneously stopped work on Monday morning in protest against both the dismissal and the broader working conditions. Approximately 40 to 50 people work at the three sites, which are concrete plants formerly operated under the name Interbeton.

The action had immediate consequences. Several construction sites were left without concrete deliveries on Monday morning, as reported by La Libre Belgique.

After roughly two hours of negotiations between unions and management, an agreement was reached. Workers will resume work on Tuesday, August 11, and the gates at all three locations remain closed on Monday with workers receiving strike pay.

The Agreement: Limits on Working Hours

The core of the agreement concerns working hours. Joris Jackers of the ACV Christian union (ACV Construction - Industrie & Énergie) outlined the key commitments: “We aim for a maximum of 11 hours per day and the rest time between 2 shifts must be 11 hours and that may not be less. We will strictly monitor that.”

However, the unions were unable to reverse the dismissal of their colleague. “Unfortunately, we could not reverse the dismissal of the driver,” Jackers said. “On that point, management did not want to budge.”

The unions say they have been raising concerns about working conditions for months. As TVL reported, workers protested against the long working days of up to 15 hours that the company demanded. Staal of ABVV expressed frustration that action was needed before management would engage: “These are problems we have been raising for months. It is regrettable that action had to be taken before management deigned to sit down at the negotiating table.”

Jackers also noted that “an accident is rarely due to a single factor,” emphasizing the importance of considering not only the accident itself but also the conditions in which employees work.

Company Response

Heidelberg Materials said it limits working time overruns as much as possible, taking into account the unpredictable nature of site work. “After constructive consultation on work organization and local operations, the dialogue will continue in the coming weeks,” Allaerts said. “We are satisfied that work will resume tomorrow.”

Broader Context: A Pattern of Labor Tensions

The strike in Belgium follows earlier labor disputes at Heidelberg Materials in the Netherlands. In January 2026, workers at the company’s Rotterdam plant staged a 24-hour strike — the second in two weeks — over stalled collective bargaining agreement negotiations between the FNV union and the employer, as reported by Aannemer. The FNV demanded a 6% wage increase while the employer offered approximately 3%.

What’s Next

Workers at the three Limburg sites will return to work on Tuesday, with the concrete agreements on working hours to be further elaborated in the coming weeks. The unions have pledged to strictly monitor compliance with the new limits of 11 hours per day and 11 hours of rest between shifts. The dismissal of the driver remains a point of contention, with the unions unable to secure his reinstatement.

As the dialogue between unions and management continues, the outcome of this dispute may serve as a reference point for labor relations at Heidelberg Materials’ operations across the Benelux region.