A physical test piece as award criterion for restoration works? Permitted — even if the assessment of craftsmanship feels subjective
The Council of State rejects the extreme-urgency suspension against the award of the 'Maçonneries' lot of the restoration of the Sainte-Croix Collegiate in Liège to the temporary association Galère / Liégeois because a 'pièce d'épreuve' — a physical test piece in carved tuffeau stone — and the accompanying methodological note, together worth 20 points out of 100, are a valid award criterion and no manifest assessment error by the jury was demonstrated.
What happened?
On 6 October 2022 the city of Liège launched an open procedure for the restoration of the exterior envelope of the Sainte-Croix Collegiate, divided into two lots: lot 1 'Toitures' (roofs) and lot 2 'Maçonneries' (masonry). For lot 2 the award framework had four criteria: price (50/100), craftsmanship demonstrated through a 'pièce d'épreuve' — a test piece in carved tuffeau stone (20/100), methodological note on site organisation (30/100), and a methodological note on stability (integrated as a sub-ranking). Two bidders submitted offers: Monument Hainaut and the temporary association Galère / Liégeois. On 29 November 2022 the jury awarded 80.08 points to Monument Hainaut and 94.57 points to Galère / Liégeois. On 30 December 2022 Liège's collège communal awarded the lot to the association; Monument Hainaut was notified on 18 January 2023. On 1 February 2023 Monument Hainaut filed an extreme-urgency suspension and raised five pleas. One core attack targeted the nature of the 'craftsmanship' criterion: according to Monument Hainaut, a 'pièce d'épreuve' is not an objective criterion linked to the subject of the contract, and the choice of the type of tuffeau to use (a French alternative, given that Belgian Maastricht tuffeau is depleted) falls outside the criterion. The Council clearly rejects this: a test piece allows the contracting authority to capture the actual craftsmanship of the contractor — exactly the kind of know-how that is crucial in restoration work on historical monuments — and the tender documents explicitly state that the test piece serves 'for the control of the finish and the quality of the execution'. The choice of the most appropriate sample of replacement stone for the planned greffon is part of demonstrating the craftsmanship that the second criterion assesses, and is therefore directly linked to the subject of the contract. A second point of contention concerned the 'methodological note on stability'. Monument Hainaut argued that a 'note de calcul' (calculation note) had to be attached to the offer, and that the association's offer did not include one. The Council answers prima facie that the tender documents mention the relevance of the calculation note as an assessment element but do not require it to be produced at the offer stage — the calculation notes are submitted for approval during execution. A third point: Monument Hainaut contested that the jury had positively valued Galère's 'pilot' role within the temporary association under the 'collaboration with lot 1 contractor' criterion. The Council answers that the jury could base this positive evaluation on concrete elements in the offer (phasing plan, identification of subcontractors, coordination at the seams between masonry and roof), and that this had nothing to do with any potential awarding of lot 1 to Galère — moreover no contractor had yet been designated for lot 1. The suspension is rejected. The administrative file and offers remain confidential at this stage.
Why does this matter?
For bidders on specialised restoration, heritage or craftsmanship contracts this is an important ruling. It confirms that a contracting authority may use physical test pieces (échantillons, pièces d'épreuve) and the methodological narrative around them as an award criterion for up to 20 % of the score. The choice of materials, techniques and visual quality of the test piece become evaluable elements — not technical selection criteria, but award criteria. Bidders who focus narrowly on price and treat the test piece superficially will lose. The ruling also confirms that an authority does not necessarily need to require a calculation note at the offer stage — that is a matter of tender design. And for those drafting such a criterion: the ruling implicitly sets the boundaries — the criterion must be clearly linked to the subject (here: craftsmanship for restoration), the assessment criteria must be explicit in the tender documents, and the jury's motivation must concretely engage with those criteria.
The lesson
If you bid on a restoration or craftsmanship contract that includes a 'pièce d'épreuve' or equivalent sample as an award criterion: handle that section with the same care as your pricing. Read the tender documents on what the jury will assess on the test piece (finish quality, material choice, narrative on the greffon methodology), choose materials that match the requirements exactly, and write a methodological note that touches every assessment element. Expect that a 20 % criterion with a wide score range (where you might score 5/20 or 15/20) has a decisive impact on the final ranking — more than a narrow cost difference.
Ask yourself
Does your tender analysis have a separate section for 'qualitative award criteria requiring physical execution' (test pieces, demo screens, pilot components)? Does your technical team's offer include a methodological note that explicitly addresses every assessment dimension? Have you justified the choice of every sample? In restoration work, for some original Belgian stones that are now depleted (like Maastricht tuffeau): do you know the currently accepted French, German or Dutch alternatives and their match on colour, grain, hardness?
About this database
The Council of State (Raad van State / Conseil d'État) is Belgium's supreme administrative court. In disputes over public procurement — from contract awards to tenderer exclusions — the Council of State is the final arbiter. The rulings in this database are summarised by TenderWolf in plain language, with practical lessons for tenderers and contracting authorities. View all rulings →