A Stochastic Approach to LCA of Internal Insulation Solutions for Historic Buildings

The Evaluation of Historic Building Energy Retrofit Projects through the Life Cycle Assessment

The built environment sector is one of the main sources of greenhouse gas emissions and resource depletion that contributes to the climate change crisis. The European Commission, in the “Green New Deal”, highlights that the sustainable regeneration/requalification of existing buildings plays a fundamental role to maximize the objective of decarbonization and resource conservation for 2050. The aim of this study was to understand how historic buildings’ energy retrofit projects can contribute to achieve this goal. In this study, we made a life cycle assessment to evaluate an energy retrofit project of Villa Vannucchi, an historic building located in San Giorgio a Cremano (Naples). The results of this application showed that the use of hemp material, for walls’ thermal insulation, significantly reduces the percentage of environmental impacts in the entire material life cycle (compared with traditional materials). This was because the plant removes a significant percentage of CO2 already from the atmosphere when it is growing. In conclusion, the assessment of different design scenarios that promote the use of innovative technologies and materials can be of high utility to designers to compare and choose efficient solutions for the sustainable/circular renovation of historic buildings.

A Software Tool for a Stochastic Life Cycle Assessment and Costing of Buildings’ Energy Efficiency Measures

This article presents a novel software tool for the assessments of life-cycle environmental impacts and costs, which is aimed to support decision-making in the design phase of retrofit interventions in the building sector. By combining Life Cycle Costing (LCC) and Life Cycle Assessment (LCA) calculations and functionalities, this tool allows evaluating the long-term trade-offs between economic and environmental performance of investment projects in energy efficiency for buildings, while accounting for uncertainties in input parameters and economic scenarios. A major novelty of the software tool is the stochastic nature of both the LCC and LCA dimensions. The LCA is implemented with Monte-Carlo methods, while the LCC accounts for the probabilistic interdependence of macroeconomic variables over time. The software also includes advanced specific tools for parametrization and sensitivity analysis. Exemplary applications are presented in order to illustrate the novelty and the functionalities of the software tool.

Evaluation of Life-Cycle Assessment Analysis: Application to Restoration Projects and New Construction in Alpine Climate, Japan

The present paper discusses the applications of life-cycle assessment (LCA) to construction works in Japan. LCA has been frequently used to assess the environmental impacts of new construction. Nonetheless, the applications of LCA to restoration have not been fully confirmed to date. It is said that historical buildings may contribute to sustainable development. Nonetheless, as for heritage buildings, since the protection of cultural value is usually prioritised, their environmental impacts may not be sufficiently explored. To this aim, this paper evaluated the environmental impacts of the restoration of heritage buildings. This paper consisted of two tasks. First, the restoration projects of heritage buildings in Japan were introduced. The restoration of two heritage houses was discussed, referring to heritage protection legislation in Japan. Second, LCA was performed on the restoration of heritage houses and the construction of contemporary houses. Environmental impacts were compared between the restoration and new construction with regard to greenhouse gas emissions and operational energy use. A focus was given to the amount of materials used. Restoration consumes a limited amount of materials compared to new construction, although the energy use of heritage buildings is considerable. The environmental impacts of restoration were quantified so that they were compared with those of new construction. The comparison indicated issues applying LCA to heritage buildings.

How Can Scientific Literature Support Decision-Making in the Renovation of Historic Buildings? An Evidence-Based Approach for Improving the Performance of Walls

Buildings of heritage significance due to their historical, architectural, or cultural value, here called historic buildings, constitute a large proportion of the building stock in many countries around the world. Improving the performance of such buildings is necessary to lower the carbon emissions of the stock, which generates around 40% of the overall emissions worldwide. In historic buildings, it is estimated that heat loss through external walls contributes significantly to the overall energy consumption, and is associated with poor thermal comfort and indoor air quality. Measures to improve the performance of walls of historic buildings require a balance between energy performance, indoor environmental quality, heritage significance, and technical compatibility. Appropriate wall measures are available, but the correct selection and implementation require an integrated process throughout assessment (planning), design, construction, and use. Despite the available knowledge, decision-makers often have limited access to robust information on tested retrofit measures, hindering the implementation of deep renovation. This paper provides an evidence-based approach on the steps required during assessment, design, and construction, and after retrofitting through a literature review. Moreover, it provides a review of possible measures for wall retrofit within the deep renovation of historic buildings, including their advantages and disadvantages and the required considerations based on context.

Historic Building Energy Audit and Retrofit Simulation with Hemp-Lime Plaster—A Case Study

Hemp-lime composite is a natural material, which is being increasingly used and studied in the construction sector, thanks to its recyclability, hygrothermal comfort and healthiness features. The aim of this paper is to test the benefits in terms of energy efficiency achieved through the use of hemp-lime composite as insulation in a possible refurbishment intervention. With the aim of extending the knowledge about the benefits achieved through from the integration of this natural material into construction production process, a real building in south of Italy was selected and a substitution of the standard gypsum-lime plaster with a hemp-lime one was simulated by means of a specific software (Termus® by Acca Sotware, Bagnoli Irpino, Italy), serving for the assessment of the energy performance. Case study analysis highlighted the good thermal insulation properties of hemp-based plaster, allowing thermal dispersion to decrease in the winter season and improve the summer performance of the walls by approximately 20% compared to traditional plaster. This results in a one-level improvement of the building in energy classification according to Italian regulation.