Application of Multiple Criteria Decision Making to Renovation of Multi-Residential Historic Buildings

Although the necessity for renovation of the existing building stock is commonly acknowledged, very low renovation rates are observed in practice. With 1% of the buildings renovated annually, it would take 100 years to upgrade the existing building stock to a more sustainable level. In most countries, incentives have so far not had sufficient impact on the rate and depth of the renovations. A very common obstacle in the decision process for building renovation is the conflict between multiple goals. In an early stage of the decision process, stakeholders have the possibility to block a renovation project without any cost.
When stakeholders act individually and the project does not meet their goals perfectly, the easiest solution is to reject it. Alongside owner decision makers and authorities, tenants and tenant associations also have a blocking power. Yet, it is rare to find a renovation project, which fulfills simultaneously and optimally all three pillars of sustainability. Multiple criteria decision making methodologies can help to improve the decision environment and handle the whole space of constraints. It therefore leads the stakeholders to find consensual solutions. In this paper, we show on a case study how existing and newly developed evaluation methods were used to determine a convenient renovation scenario accepted by all the stakeholders. The building is a multi-residential historic building constructed in the early twentieth century. EPIQR+ method was used to evaluate the building deterioration, energy performance of refurbishment scenarios and the renovation costs. PETRA method was used to evaluate the
quality of the historic building conservation. It was also used to evaluate the economic impact on tenants and the impact on the value of the building. In order to assess the indoor environment quality and the comfort of use, questionnaires were distributed to the tenants. Finally, so as to provide the stakeholders with a comprehensive comparison between different possible scenarios, a synthesis of the evaluation of all criteria was made with HERMIONE multiple criteria aggregation method. The results of the holistic multiple criteria analysis change the perception of the stakeholders and their attitude towards the renovation of the building
envelope.