Historic, listed, or unlisted, buildings account for 30% of the European building stock. Since they are complex systems of cultural, architectural, and identity value, they need particular attention to ensure that they are preserved, used, and managed over time in a sustainable way. This implies a demand for retrofit solutions able to improve indoor thermal conditions while reducing the use of energy sources and preserving the heritage significance. Often, however, the choice and implementation of retrofit solutions in historic buildings is limited by socio-technical barriers (regulations, lack of knowledge on the hygrothermal behaviour of built heritage, economic viability, etc.). This paper presents the approach devised in the IEA-SHC Task 59 project (Renovating Historic Buildings Towards Zero Energy) to support decision makers in selecting retrofit solutions, in accordance with the provision of the EN 16883:2017 standard. In particular, the method followed by the project partners to gather and assess compatible solutions for historic buildings retrofitting is presented. It focuses on best practices for walls, windows, HVAC systems, and solar technologies. This work demonstrates that well-balanced retrofit solutions can exist and can be evaluated case-by-case through detailed assessment criteria. As a main result, the paper encourages decision makers to opt for tailored energy retrofit to solve the conflict between conservation and energy performance requirements.

In school buildings, natural light has considerable physiological benefits, and increases energy efficiency while reducing the operational energy consumption of buildings. It is thus crucial to maximize the amount of daylight, as well as to improve its quality, in educational premises. In Italy and other European countries, many historic buildings are reused as school buildings, changing their original function. This process of adaptive reusing is one method for conserving heritage buildings, however sometimes this process sacrifices the quality of daylight and well being of pupils. It has therefore become apparent that it is difficult to reconcile the cultural value of historic buildings with comfort standards. This study aimed to investigate the natural lighting performance of a school located in an historic building, and proposes different technological solutions to improve the visual comfort in classrooms whilst also respecting the cultural value of built heritage. Daylight performance was carried out in a representative classroom in the ‘Caserma Gaetano Abela’, an historical building located in Siracusa (Italy). A daylight model built in Radiance was first validated against an illuminance measurement campaign, and was then used to run detailed dynamic simulations. Climate Based Daylight Modelling (CBDM) metrics were used to show the achievable improvements in visual comfort conditions by means of proposed retrofit interventions. These interventions may also be used in other areas of southern Europe with similar climatic and constructive/distributive characteristics of architectural heritage.

Architectural integration of plants in historic buildings has always been a much debated topic. Nowadays it is enriched with an ethical connotation linked to sustainability/environmental responsibility (reduction of energy consumption, using renewable energy sources, reduction of CO2 emission, etc.).This paper deals with the theme of integration of solar technologies in buildings and focuses on difficult and problematic relationship between the physical conformation of the plant and the cultural values of the building itself (especially on the cultural value of the image of built heritage). It wants to highlight how the satisfaction of requirements linked to the protection of these buildings, cultural resources of every city and nation, could constitute as an promoter of technological innovation.After making an investigation on major existing products on the solar technology, through a case study of residential historical building, we present the preservation criteria and guidelines that laying down principles for the validation of each existing technology on the market

The legacy of built heritage is one of the most critical questions of our time—the objective of preserving its immaterial values and exploiting its original vocation brings about challenges related to the history, the identity, and the quality of life of the concerned territory. This especially applies to religious buildings given their strong bond with collective memory. The aim of this research is to determine whether allocating new uses that pursuit social benefits for the community is a possible implementation of the aforementioned purposes and whether it better addresses a broader view of sustainable development, which encompasses equity and well-being. The methodology combines careful knowledge of the building, comparing residual performances of the fabric with new functions. We present a case study, with focus on healthcare-related accommodation facilities and the issue of healthcare migration, which aims to convert a dismissed capuchin convent, located in Villagonia (Taormina, Italy), into a shelter house to host families whose relatives are being treated at the neighbourhood medical centre. This proposal shows that heritage buildings, especially religious ones, have outstanding material and immaterial potential and, through good reuse practices, they provide a valuable opportunity to address the overarching objective of social sustainability.

Clay has a low environmental impact and can develop into many different products. The research presents two different case studies. In the first, the clay is the binder of raw earth doughs in order to produce clay-bricks. We investigate the effects of natural fibrous reinforcements (rice straws and basalt fibers) in four different mixtures. From the comparison with a mix without reinforcements, it is possible to affirm that the 0.40% of basalt fibers reduce the shrinkage by about 25% and increase the compressive strength by about 30%. Future studies will focus on identifying the fibrous effects on tensile strength and elastic modulus, as well as the optimal percentage of fibers. In the second study, the clay, in form of brick powder (“cocciopesto”), gives high alkaline resistance and breathability performance, as well as rendering and color to the plaster. The latter does not have artificial additives. The plaster respects the cultural instance of the original building. The research underlines how the use of a local (and traditional) material such as clay can be a promoter of sustainability in the contemporary building sector. Future studies must investigate further possible uses of clay as well as a proper regulatory framework.