A Model for Determining a Discount Rate in Market Value Assessment of Buildable Areas Subject to Restrictions

At the European level, the exercise of building rights on areas that general planning tools have considered to be buildable is allowed only upon the issuance of a specific building permit. The legal procedures used to obtain the above-mentioned building permit can be largely affected by some constrains able to limit—and occasionally prevent—the exercise of the building rights (even if they are established by a general planning tool). Therefore, in the evaluation of buildable areas without building permit, the uncertainty relating to the presence of constraints/limitations that require a specific authorization issued by the competent authorities need to be considered as a part of the urban risk. This article is thus based on the assumption that to assess buildable area without building permits must be considered as the actual condition it is found in, and therefore its limitations and the time necessary for the building to be built actually and not just “potential”. To implement this approach, a model for determining a discount rate in market value of buildable areas subject to restrictions (limitations and constraints) has been structured.