A construction worker under joint committee (JC) 124 is entitled to 12 rest days in 2027. In Flanders, the first one falls on 30 March 2027. Three public holidays fall on a weekend and the joint committee replaces them with a working day. You post the notice with those replacement days before 15 December 2026.
Construction leave Belgium 2027: the rest days per regime
For most of the year, a construction worker works 40 hours a week. The rest days (ADV days) bring that back to an average of 38 hours over the year. Six rest days are in the new working time reduction agreement of 2 July 2026, which enters into force on 1 November 2026 and runs until 31 December 2028. At the same meeting, the joint committee gave its advice on the other six days. Those only become binding through a royal decree, and that decree had not yet appeared in the Belgian Official Gazette on 6 October 2026.
Which dates apply depends on where the establishment is. Regime A applies in the Flemish Region and the German-speaking Community, regime B in the Walloon Region. For an establishment in Brussels, the company chooses.
| Rest days 2027 | Regime A (Flanders) | Regime B (Wallonia) | Basis |
|---|---|---|---|
| Spring | Tuesday 30 March 2027 and Wednesday 31 March 2027 | Tuesday 4 May 2027 and Wednesday 5 May 2027 | agreement |
| November | Tuesday 2 November 2027 to Friday 5 November 2027 | same days | joint committee advice |
| November | Friday 12 November 2027 | same day | joint committee advice |
| Before Christmas | Friday 24 December 2027 | same day | joint committee advice |
| Year end | Tuesday 28 December 2027 to Friday 31 December 2027 | same days | agreement |
A rest day suspends the employment contract. You pay no wages: Constructiv pays the worker a fixed allowance. The agreement works with a winter period from 24 December 2027 to 7 January 2028. A notice period you served as the employer is suspended during the rest days in that period.
Replaced public holidays in construction in 2027
In 2027, 1 May falls on a Saturday, 15 August on a Sunday and Christmas on a Saturday. The joint committee for construction replaces them with Friday 7 May 2027, Friday 13 August 2027 and Monday 27 December 2027. The Federal Public Service Employment has not yet added that decision to its official list. How to draft the notice and what applies in other sectors is in our article on the replacement public holiday.
Construction leave in East Flanders in 2027: a recommendation, not an agreement
The summer leave in construction is not in any collective agreement. Employer and employee organisations agree on a recommendation per region.
- East Flanders, except the canton of Lokeren: from 12 July 2027 to 2 August 2027, with 1 April 2027 and 2 April 2027 as days off and 3 days the worker chooses by agreement.
- Canton of Lokeren: from 19 July 2027 to 9 August 2027, with the same April days off and the same three days to choose.
That adds up to the 20 statutory holiday days of a full-time worker on a five-day week: 15 working days in summer (21 July is a public holiday), 2 in April and 3 to choose. With Easter Monday on 29 March, the rest days at the end of March and the April days off, a site in East Flanders stands still for the whole week after Easter.
A recommendation does not bind your company automatically. The annual holiday rules set the order: a decision of the joint committee, otherwise the works council, otherwise an agreement with the union delegation or, if there is none, with the employees. Failing that, you agree on the holiday with each employee.
What to settle in December 2026
- Establishment in Flanders and regime A suits you? Then you have nothing to do.
- Prefer the other regime? With a union delegation, you conclude a written agreement by 1 December 2026. Without a delegation, you decide before 1 December 2026 and post the notice before 15 December 2026. Report the choice to Constructiv.
- Establishment in Brussels? Choose regime A or B: with a delegation in an agreement by 1 December 2026, otherwise you decide yourself before 15 December 2026 and post the decision before that date. Report this to Constructiv as well.
- Post the notice with the 2027 replacement days before 15 December 2026 and attach a copy to the work rules.
- Set the collective holiday, following the recommendation or with your own dates, in the way described above.
New in January 2027: the ConstruBadge goes digital
Your workers will no longer receive a plastic ConstruBadge for 2027. From 1 January 2027, the badge is in the MyConstructiv app. If you use the badge as identification on site, ask your workers to install the app in advance. More on the sector rules in our guide to JC 124 and on the construction sector page.
What Business Centrum does for you
We enter the rest days, the replacement days and your collective holiday for 2027 in the payroll, with the right codes in the DmfA declaration so that Constructiv pays the rest days correctly, together with Acerta. We prepare the replacement day notice for posting and track the December deadlines. Day-to-day leave management sits in leave and absences. Do you have an establishment in Brussels or want to switch regime? Have the choice checked before 1 December 2026.