Assessment of the weighted average cost of ecological-environmental equipments in urban transformation processes

The process of renewing urban plans always focuses on incorporating the sustainability paradigm into strategic initiatives to counteract climate change. A regulation aimed at implementing Ecological-Environmental Equipment to compensate and mitigate the environmental impact of direct interventions, such as new construction, redevelopment, regeneration, and repurposing, has been approved by the new Cesena-Montiano Inter-municipal Urban Plan. These are virtuous cases selected by the Municipality as they respond to the site-specific characteristics of the urban context under consideration. To facilitate their implementation, the Regulations require the estimation of the Economic Countervalue (ECV) using the Bill of Quantities (BoQ).To support the weighted assessment of the ECV to be applied to equipment in the scenarios given in the Plan, this work describes the development of an economic evaluation approach that combines the BoQ with the Analytic Hierarchy Process (AHP). A BoQ was created for every design solution to calculate the parametric unit cost. The AHP assesses the importance of the macro-categories (permeable surfaces, water, vegetation, and technology) and sub-categories (specific solutions) in the Regulation Abacus to weight the average unit cost. To determine the aspects’ relevance, a survey was given to a group of municipal technicians with various specialities. Then, using the appropriate weights, the average unit cost of the design solutions was compared to the cost of each sub-criterion. The total average unit cost obtained from the sum of the partial costs gives the weighted average unit cost of the ecological and environmental equipments, equal to € 84.99/sqm.