In November, the IEA SHC Programme finalized its work on Renovating Historic Buildings Towards Zero Energy (SHC Task 59/EBC Annex 76). To learn first-hand about the Task’s impact on historic buildings, we asked Alexandra Troi, the Task Operating Agent, to share some of her thoughts on this multi-year project.

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.

This publication is in Turkish, with a link to the English translation at the top.

Lila Angelaka, Senior Technical Officer of Technical Research Team from the Scottish Historical Environment, points out that the restoration of the historical environment and historical buildings, especially with local and traditional materials, reduces the carbon emitted during both procurement and production of the material: “We advocate to reuse of existing buildings and their refurbishment. Many traditional buildings have an inherent, in-built resilience to climate impacts”.

ekoiq.com/2020/12/09/our-heritage-is-the-unique-factor-that-can-reduce-carbon-emissions/

The integration between solar energy systems and building components is highly critical in sensitive heritage contexts. On the one hand there is the need for finding a balance between the preservation of the aesthetic appearance and the historical values, but on the other hand, finding the space where to effectively integrate the systems might be quite challenging. 

This article introduces chapter 1 "Evolution of BIPV in 40 years: architecture, technology & costs" of the BIPV Status Report 2020 "Building Integrated Photovoltaics: A practical handbook for solar buildings’ stakeholders", a joint publication SUPSI Institute of Applied Sustainability to the Built Environment (ISAAC) and the Becquerel Institute.

solarchitecture.ch/bipv-in-dialogue-with-history/

È possibile conservare edifici del passato in modo rispettoso della loro essenza e al contempo migliorarne l'efficienza energetica? Una domanda che concerne non solo i beni culturali riconosciuti, ma anche gli stabili di pregio costruiti negli scorsi decenni, secondo standard diversi da quelli attuali.

Climate change will affect future hygrothermal performance of buildings. This could lead to higher risks regarding energy optimization, thermal comfort and historic building conservation depending on the local climate, building construction and retrofit solutions adopted. This paper explores the risks brought by climate change on a typical residential historic building of South Tyrol. The results obtained show that, although the climate warming will reduce the future heating energy demand, an improvement of buildings' energy performance will still be necessary to increase sustainability and ensure their continued use. Natural ventilation would suffice to prevent overheating in the studied location, but a further analysis is needed for warmer alpine regions. Regarding the moisture-related risks for the historic construction, mould growth should be considered when retrofitting a wooden wall and frost damage should be carefully studied in the case of sandstone walls.

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A short article with information about general maintenance of tenement flats and communal areas within Scotland. This includes links to further information and common repairs.

The proper simulation of the hygrothermal behaviour of historical buildings is a challenging task with several implications regarding the evaluation of indoor thermal comfort and the suitability of retrofit strategies that comply with the conservation of cultural heritage. An inaccurate simulation may lead to inadequate conclusions, which could result in inappropriate and dangerous actions for the preservation of the heritage buildings.

The present work reviewed the main approaches used by researchers for building performance model validation with special reference to historical buildings based on microclimatic parameters, highlighting the main advantages and drawbacks of the different methods reviewed. Finally, recommendations to properly carry out the model validation based on microclimatic parameters have been provided. The collected information may be useful to different subjects (e.g. designers, energy auditors, researchers, conservators, buildings’ owners and policy makers) and can drive suitable and reliable retrofit and maintenance interventions.

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Building dynamic simulation tools, traditionally used to study the hygrothermal performance of new buildings during the preliminary design steps, have been recently adopted also in historical buildings, as a tool to investigate possible strategies for their conservation and the suitability of energy retrofit scenarios, according to the boundary conditions.

However, designers often face with the lack of reliable thermophysical input data for various envelope components as well as with some intrinsic limitations in the simulation models, especially to describe the geometric features and peculiarities of the heritage buildings. This paper attempts to bridge this knowledge gap, providing critical factors and possible solutions to support hygrothermal simulations of historical buildings.

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Improving the energy performance of historic buildings has the potential to reduce carbon emissions while protecting built heritage through its continued use. However, implementing energy retrofits in these buildings faces social, economic, and technical barriers. The purpose of this conceptual paper is to present the approach of IEA-SHC Task 59 to address some of these barriers.

This research describes the methodology applied to carry out the monitoring campaign on the Milan Duomo, one of the biggest Cathedrals in Italy. The campaign was carried out by means of non-invasive measuring instruments, in order to keep the building intact and ensure the smooth running of the activities. In a second stage, sensors for the long-term monitoring were installed according to the most significant and accessible points inside the Cathedral.

The data collected during one year of monitoring was used to characterize the hygrothermal behaviour of the Cathedral, in order to assess the risks for the main materials which sacred objects, artworks, organs, sculptures and furnishing are made of.

Historic building heating and, in particular, church heating represents a challenging task because many objectives have to be reached simultaneously; in facts, adequate thermal comfort levels have to be guaranteed for the occupants while ensuring an optimal internal climate suitable for the preservation of valuable and often fragile building components and artworks. Moreover, current requirements for sustainability impose to make efforts, where possible, to minimize the amount of energy needed and the consequent environmental impact. For such reasons, the present work addresses in detail the church heating topic, by analysing different feasible strategies and developing subsequently an original technology, able to combine energy efficiency and cultural heritage preservation aspects.

Il rispetto per gli edifici storici può portare a escludere a priori la possibilità di introdurvi nuove tecnologie per il risparmio energetico. Con l'intervento al Castello di Doragno, lo studio deltaZERO mirava a ripristinare «l’anima» dell'edificio dotandolo al contempo di tutte le tecnologie necessarie per garantire le odierne esigenze di comfort.