The issue of value and quality of buildings has long been assessed via financial consider-ations, summarized as a value of the total return for investors. The main problem of this implicit assumption is that the price is supposed to reflect the global quality of the good. However, the real estate market is not transparent, the good is complex and the information on the quality dimensions of properties are hardly accessible. These market characteristics lead to suggest that price is less a reflection of quality but rather, price creates the idea of quality for markets players. Indeed, prices are based on similar properties more than a in depth study of quality. This can lead to markets failure (bubble and disconnection with the reference value). To adress this issue, we propose to develop a methodology providing a value of a building, based on the quality dimensions. In order to assess this quality, some specific approaches exist (such as Breeam, HQE, Wired...) but they are partial and oriented toward a specific goal (environmental, connectivity). Other exist but are arbitrary and not based on the market judgment. We propose a new approach, called REQUAL (Real Estate QUALlity) procedure where objec-tive characteristics of quality are judged by nearly 80 stakeholders and decision makers, and doing so they create the reference value of the property, irrespective to the price. In this paper, our methodology is proposed to reveal 1) the main characteristics of quality, using both tangible and untagible dimensions from qualitative interviews, 2) the judgment of the market players on the implicit combination of these dimensions to compose a unique quality score via an experimental procedure including more than 60 buildings evaluated by expert.
