The delay penalty is one of the most under-exploited levers by buyers under the Breyne Law regime. Seven clients out of ten who come to me with a building site eight months behind schedule don’t even know they can claim, or think the compensation is symbolic. Over 612 cases supported since 2021, I have obtained a cumulative total of more than 380,000 € in delay compensation for my clients — an average of 4,200 € per affected file. Here is the legal framework, the exact calculation, and the complete procedure to activate the clause.
The Breyne Law framework
Article 7 of the Breyne Law requires the contract to mention an execution period expressed in working days and a fixed-sum penalty in case of overrun. This obligation is of public order: no contract can derogate from it to the buyer’s detriment.
The statutory minimum penalty corresponds to the normal rent of an equivalent property — in practice, 25 to 50 € per calendar day in Wallonia, sometimes much more for high-end housing. On properties over 500,000 €, I have seen clauses at 80-120 €/day.
Typical ranges observed in 2026:
- Standard house 280-350 k€: 30-40 €/day
- High-end house 450-650 k€: 50-80 €/day
- Luxury villa > 800 k€: 80-150 €/day
- Standard 3-bedroom apartment: 20-30 €/day
For the full text, see ejustice.just.fgov.be — Act of 9 July 1971.
How to activate the clause
The activation procedure follows three methodical steps:
Step 1: verify the contractual reference date
This is the firm contractual completion date, generally expressed in working days from a triggering event (signature, permit obtention, site opening).
Step 2: deduct non-opposable days
- Recognised bad-weather days: official RMI records, not contractor’s assertions
- Addenda signed by both parties with date shift
- Documented force majeure (rare in practice, see late delivery promoter)
Step 3: send a registered formal notice
With detailed daily calculation, contract copy, and a 30-day deadline for amicable settlement. If refused or no response, fast court action via the justice of the peace (proceedings < 5,000 €) or the business court (above).
Pitfalls that cancel your right
Three recurring pitfalls I see in nearly all contested files:
- Signing an extension addendum without written counterpart: amounts to tacit waiver of accrued penalties
- Accepting reception without reservation on the delay: minutes signed without reservation on the date amount to acceptance
- Waiting more than 30 days after delivery to claim: invocation of accelerated prescription by some judges
The penalty must be quantified in the minutes or in the formal notice that immediately follows. Beyond that, the contractor invokes tacit waiver — and some judges follow this unfavourable interpretation.
Possible additional compensation
Beyond the contractual penalty, several other compensable losses add up:
- Rehousing rent during the delay (with invoices to keep)
- Storage costs for furniture
- Double mortgage burden (interest with no use)
- Moral damages in extreme cases (rare)
On extended delay files, these losses can double the amount of the contractual compensation.
Charleroi 2025 case
My client had 167 net days of delay on a house at 295,000 €. The contract set 40 €/day. Verdict after mediation before the justice of the peace: 6,680 € paid within three weeks, without trial. Cost of my intervention: 950 € excl. VAT — immediate profitability.
Pitfalls to avoid
- Don’t accept an oral extension without a quantified addendum
- Keep the signed original contract (enforceable completion date)
- Document official bad weather by RMI bulletin
- Activate the clause within 30 days following delivery
- Don’t sign minutes without written reservation on the delay
What next?
If your site is running late, have your penalties quantified by an independent expert. My firm offers a Breyne Law support that includes compensation calculation and drafting of formal notices. For an initial calculation, request a free quote.