Evaluation of retrofitting concepts from a life cycle perspective
In the LCBuild project, both environmental and social aspects related to the retrofitting of housing are considered from a life cycle perspective. On the one hand, life cycle analyses (LCA) are performed to gain insights in the environmental impacts of different materials, systems or renovation principles. On the other hand, social aspects related retrofitting are evaluated and a social life cycle assessment methodology is developed.
Environmental analyses of partner projects
LCA has been used to calculate the environmental impacts of the subsystems studied by different project partners, particularly: lightweight flooring components (project LightComp), innovative external thermal insulation composite systems (project innov-ETICS), industrialized envelope systems for façade renovation (project AIM-ES), the urban windmill concept (project Wintegrate) and energy storage concepts (project MESB). The results of these LCA exercises bring an added value to the design process of these systems, as they provide insights in how to reduce environmental impacts and optimize the proposed technologies from an environmental point of view. Additionally, results deliver information for benchmarking against alternative systems.
Deep renovation or demolition: environmental and financial impacts
The environmental and financial impact of different construction scenarios (renovation versus demolition and new construction) were studied in a building case study using the LCA (Life Cycle Assessment) and LCC (Life Cycle Costing) methodology. The reference scenario for the case study was the deep renovation of a residential building in Schaarbeek where a completely new wooden frame structure was installed from the inside (a box-in-box construction). For the selected case study, the scenario considering the demolition and new construction leads to a higher total environmental impact and higher life cycle cost than the alternative scenarios considering renovation. However, given the additional floor space that can be created in a new construction, this option seems to be a valuable one, especially in an urban context where space is scarce.
Methodology for social life cycle assessment of building renovation
Social aspects must be included into the assessment of buildings. Currently, the emerging technique of social LCA (s‐LCA) does not allow assessing retrofitting works from a life cycle perspective. LCBuild proposes relevant criteria for the context of Brussels. The development focuses to assist major decision-making at the level of the region (public organisms, consultants, architects, etc.) for the optimization of measures to foster more sustainable retrofitting practices.
The review of existing evaluation tools and methodology developments allowed to identify available indicators and impacts to consider (LCI/data inventory, LCIA/impact assessment). New indicators have been developed to address relevant context-specific issues (housing conditions, affordability of works, fuel poverty, etc.) and sector-specific issues (unemployment, deteriorated working conditions, etc.) Characterization models are proposed to analyze impacts on health (of workers and users) and on prosperity (of society at large, of the Region as institution and of households).
In combination with environmental LCA, the proposed s-LCA methodology can support decision making processes towards more sustainable retrofitting practices in the Brussels Capital Region.