Energy Performance Of Historic Buildings Research Articles

Historic building energy conservation with wooden attic using vacuum insulation panel retrofit technology

The envelopes in historic buildings must be preserved as aging historic buildings continue to be used. Conservation is necessary to improve the energy performance of historic buildings. The target building of this study has an exposed rafter structure. Modern historical buildings in Korea do not have a passive retrofit, which is insulation. The passive retrofit covering the roof structure needs to be applied taking into account the original protection of the exposed rafters. This study aims to examine the energy improvement effect of a historic building with a roof with an exposed rafter structure. Considering the characteristics of the building, a vacuum insulation panel (VIP) retrofit technology is used instead of general insulation. The VIP is thin and has high heat resistance, so there is little damage to the envelope of historic buildings, and the U-value of the existing roof layer is reduced by 88%. By applying retrofitting technology, the annual energy consumption of the top floor was improved by 55%. Cooling on the top floor showed an improvement of 29.87%. The largest energy savings occurred in May at 49%. This is because the VIP retrofit technology is applied in the form of external insulation. External insulation lowers heat storage owing to solar radiation. The developed VIP was suitable for Korea's preservation considerations and building energy conservation considerations.

Existing tools enabling the implementation of EN 16883:2017 Standard to integrate conservation-compatible retrofit solutions in historic buildings

• Review of computer-based decisional tools for conservation-compatible energy retrofit. • Collaborative information-search methodology. • Three levels of action (single building component, whole building, district level). • Analysis of tools’ structure, aim, limitations and link to EN16883 procedure. • Overview of potential future developments of the tools to enable the use of EN16883. The heterogeneity of historic buildings and environmental conditions, as well as the variety of possible technical solutions, introduce great challenges to the decision-making process for the definition and implementation of energy retrofit projects. The variety of stakeholders involved in the process, each bringing specific skills and goals, further add to this complexity. How can the decision be finalised when multiple and often conflicting objectives and different stakeholders are involved? In this context, the European Standard EN 16883:2017 provides guidelines to improve the energy performance of historic buildings while respecting their heritage significance. It presents a normative working procedure to select conservation-compatible retrofit solutions, which is based on a step-by-step investigation, analysis and documentation of the building. However, the recommendations provided in the Standard remain at a general level and it is the task for the stakeholders to tailor the intervention to the specific case. This paper investigates how the implementation of the EN 16883:2017 can be enabled by adopting a selection of existing computer-based tools to support the identification, assessment, and selection of retrofit solutions in historic buildings. To this end, a number of tools were analysed, highlighting their advantages, input data, outcomes and main limitations, in relation to their possible use in support of the implementation of the Standard procedure (or steps of it).

Integrated retrofit solutions for improving the energy performance of historic buildings through energy technology suitability analyses: Retrofit plan of wooden truss and masonry composite structure in Korea in the 1920s

Building energy consumption and carbon emissions must be reduced to decrease the rate of global warming. To improve the energy efficiency of historic buildings, energy retrofitting can serve as an effective strategy. Retrofitting historic buildings is difficult due to the conflict between the historical value and usefulness of the building, but a modern scientific approach can help ensure that valuable historical records and artifacts remain protected and available. In addition, the retrofit of historic buildings can contribute, although a small part, to reducing carbon emissions nationally, and can have a symbolic meaning as a combination of history and modernity.This paper proposes a package of appropriate measures to improve energy efficiency, reduce the energy consumption of buildings, and preserve regularly used historic buildings for 100-year-old wooden truss and masonry composite structured historic buildings in Korea. The proposed measures are applied to most historic buildings in Korea built in the 1920s and have the potential to improve building performance. A new approach to applying energy technology to historic buildings is proposed. The energy application suitability analysis process was established by integrating three analysis techniques: the energy-saving effect analysis technique, historical value impact evaluation technique, and economic analysis technique. To achieve an appropriate retrofit plan, the condition of a building was evaluated through on-site diagnosis. Thermal transmittance rate assessments, temperature, and humidity monitoring, and infrared thermal imaging analyses were performed to evaluate the building's condition. Consequently, thermal transmittance rates for the wall and roof of the historic building were 1.18 W/m2K and 1.67 W/m2K, respectively, which indicated a risk of excessive energy consumption and condensation. Then, the suitability of each energy technology was evaluated by analyzing its economic feasibility and impact on the historical value and by simulating the reduction in energy consumption of the building. Thereafter, based on the analyses, the energy technologies deemed suitable were integrated to form an energy-efficient retrofit package, and an appropriate solution was elucidated. In conclusion, the package with the lowest impact on the historical value and the highest energy reduction decreased the total energy consumption by 15.9%. According to the results of this study, the process and package solutions proposed in this study are appropriate measures for historic buildings built in the 1920s in Korea, and can be a strategy with the potential to reduce carbon emissions and energy.

Impact of climatic parameters on rain protection layer design for refurbished historic buildings

The application of interior insulation systems consistently increases energy performance of historic buildings, but also severely affects the drying potential of their envelopes reducing the evaporation potential towards the internal side. This reduction is even more critical in façades interested by a significant amount of driving rain. To face this problem, current recommendations and standards suggest the replacement of the original plaster with a “water repellent” one especially in climates with a high yearly horizontal precipitation. However, since this kind intervention represents a big economic and environmental cost, more specific studies are needed to identify whether it is always necessary. In fact, current approach excludes the impact of solar radiation, which may play a significant role for evaporation phenomena. Moreover, wind effect may be taken into account by considering the wind driven rain instead of horizontal rain amount. In order to investigate these hypotheses, this simulation-based study analyzes hygrothermal performances of an internally insulated wall in several European climates and latitudes, with similar annual precipitation and different solar radiation amount and wind conditions. Results show that considering wind action is important to give a more precise estimation of the effective rain impacting the façade. Moreover, water repellent exterior plasters could be avoided in façades with consistent amounts of solar radiation. Consequently, there is currently the need of a more elaborated method for identifying the necessity of replacing the historic external plasters; this method should include external climate factors, as e.g. solar radiation and wind action.

Energetic refurbishment of the historic windows of the listed heritage building Alte Schäfflerei and its influence on the overall energy balance

This study examines compatibility of monument conservation and modernization of historic windows of old buildings on the example of the Alte Schäfflerei (Old Cooperage) housing the Fraunhofer Centre for Conservation and Energy Performance of Historic Buildings at Benediktbeuern monastery. Several historic windows are extended to box-type windows and examined in detail. The calculation of the thermal bridges and the resulting U-values of the windows as well as the linear thermal bridge heat loss coefficients result in a reliable estimation of the thermal behaviour of the box-type windows. Via measurements of the surface temperature and heat fluxes on a box-type window the thermal resistance and heat transfer coefficient are estimated. The heat transfer coefficient is calculated in accordance to DIN 10077 with simple and detailed calculation and compared to the estimated calculation of simplified measurements. The energy efficiency of the whole building of the Old Cooperage is calculated in accordance to DIN V 18599 and shows the rate of heat losses of the windows compared to the overall energy demand of the building. For this purpose, the Old Cooperage is implemented with a hypothetical historic usage in DIN V 18599.

The Alte Schäfflerei at Benediktbeuern Monastery – Conjunction of Architectural Conservation and Energy Performance Improvement in a Historic Buildings

This paper gives an introduction into the research and measures of monument conservation and energy performance improvement of the Alte Schäfflerei (Old Cooperage) in the monastery of Benediktbeuern in upper Bavaria, Germany. The works started in 2010 when a contract was made between the Monastery and the Fraunhofer Gesellschaft to establish the “Fraunhofer Centre for Conservation and Energy Performance of Historic Buildings”. Both, resource and energy efficiency are approaches that are in the focus of the research. Moreover, all measures should comply with monument preservation rules and respect the original substance. The calculation of the impact of different energy saving measures like the improvement of the historic windows, internal and external wall insulation, attic and floor insulation as well as the use of renewable energies from the central power station of the monastery on the overall energy demand is presented.

Assessing and enhancing EN 16883:2017

This paper describes the work undertaken within the international project IEA SHC Task 59 Renovating Historic Buildings Towards Zero Energy to produce a handbook for the planning of energy retrofits in historic buildings. The handbook is an attempt to increase use and usability of the European standard EN 16883:2017 - Conservation of cultural heritage -Guidelines for improving the energy performance of historic buildings. The standard provides a decision roadmap for how energy efficiency measures can be identified that both respect the heritage values of the building and improves the energy performance. It also provides general information about energy efficiency in historic buildings. There has been a lot of interest in this standard from researchers in the field of energy efficiency in historic buildings, but it has not been widely used in practice. The first part of the paper summarises an assessment of the use, or lack thereof, of the standard. The assessment is based on nine European case studies that identify how the European standard can be complemented with additional resources, examples and guidance. In the second part the work with a handbook complementing the standard is outlined, and recommendations to future revisions of the standard are suggested.

Improving Energy Performance of Historic Buildings through Hygrothermal Assessment of the Envelope

The intervention on historic buildings through building energy retrofitting has become one of the current challenges of improving energy efficiency. Nonetheless, this building typology presents certain complexities. Among them, one of the most relevant is the protection on their façades due to the historical and/or artistic values of a given façade and, therefore, the addition of external thermal insulation is restricted. However, at the same time, in several of those buildings indoor surfaces do not present that architectural value, and then internal thermal insulation becomes a promising strategy for improving their thermal performance. Nevertheless, its application must be carefully evaluated to avoid possible pathologies caused by moisture problems. This paper aims to identify constructive solutions for interior insulation of walls free from moisture problems. For this purpose, a comprehensive analysis of a series of constructive solutions based on internal insulation has been carried out through hygrothermal simulations. The results show how the application of water-repellent impregnation becomes essential to guaranteeing the integrity of the envelope. In addition, the combination of insulations with or without inner membranes, such as smart vapor retarders or vapor diffusion barriers, has been evaluated detecting the solutions that best fit the objective. Finally, taking advantage of the great potential of 2D simulation tools, the post-processing of the data has been performed to apply the wood decay model, and thus assess the behavior of a very conflictive point in this type of intervention, i.e., the wooden beam-ends. The results in this critical point have shown how the application of the proposed constructive solutions becomes essential to guarantee the integrity of the element and how the application of traditional solutions could lead to a hazard that must be avoided.

Integrated Retrofit Solutions for Improving Energy Performance of Historic Buildings Through Energy Technology Suitability Analyses

Integrated Retrofit Solutions for Improving Energy Performance of Historic Buildings Through Energy Technology Suitability Analyses

Analysis of the Thermal Retrofitting Potential of the External Walls of Podhale’s Historical Timber Buildings in the Aspect of the Non-Deterioration of Their Technical Condition

The paper discusses thermal quality improvement in historic buildings. It is based on a case study of a wooden historical building in an architectural style typical of Zakopane, located in the Podhale region of Poland. The building’s historical value and timber structure prevent the application of typical thermal retrofitting solutions. This paper presents an analysis of the possibilities of the improvement of energy performance of a historic building (villa) which included: a review of the available energy performance improvement solutions applicable to this type of building, with a particular focus on applying internal insulation; a technical condition assessment using non-invasive methods, the identification of problematic areas in terms of the thermal retrofitting of buildings with timber walls and decks; in situ tests: thermovision tests which showed the places with temperature distribution field disturbances in the building’s envelope, focusing on thermal bridges; measurements of actual thermal transmittance coefficients for extant partitions; measurements of the building’s airtightness and the microclimate in selected rooms; numerical analysis: an assessment of the influence of the thermal bridges on the building’s existing condition, an analysis of water content changes in wall systems post-insulation. The presented approach enables the improvement of the energy performance of timber historical buildings while preserving the historical value of its architecture. It is innovative because it tries to fill in a research gap concerning a lack of relevant guidelines in Poland. The research questions that the authors asked were as follows. Is it possible to improve the thermal insulation of a building’s wooden walls without adversely affecting the building’s technical condition? With regard to the necessity to meet nZEB (nearly zero energy building) standards, is it feasible to improve the timber walls of historical buildings? The study found that under the correct assumptions and while maintaining a responsible approach to design, it is possible to improve the energy performance of historical buildings without interfering with historical heritage.

Internal wall insulation with a new aerogel panel: SLENTITE®for energetic retrofit in historic buildings

We present two recent test case application examples of a new high-performance insulation panel with product name SLENTITE®used as core element of a rendered internal wall insulation system. The first case study refers to the 18th-century building Alte Schäfflerei now the Fraunhofer Centre for Conservation and Energy Performance of Historic Buildings, at the monastery Benediktbeuern, southern Germany, where SLENTITE®was applied in 11/2017. The second test case was installed in 04/2019 in a heritage building situated in the historic center of Luxembourg. In Benediktbeuern, a single layer of insulation material was chosen, in Luxembourg we applied two layers of insulation. In both cases, detail work around the windows was a main task and we gained experience on product processing under real conditions. In terms of indoor room usage, the object in Benediktbeuern is used as exhibition hall with rare traffic and well controlled climate, whereas the object in Luxembourg is used as meeting room without climate control. Measured data of 20 months from the object in Benediktbeuern and first impressions of the performance in Luxembourg are discussed.

Environmental and economic benefits of optimal insulation thickness: A life-cycle cost analysis

The enhancement of energy performance of historic buildings is not a completely resolved theme because both the tools and European directives available to the designer are mainly designed to meet the needs of the new buildings. To improve the energy efficiency of this buildings built without technical installations and designed to exploit the climatic characteristics and local resources, it is necessary to investigate the key parameters that constitute the building envelope. This study presents a multidisciplinary approach allowing to compare the optimum insulation thickness determined from the transmittance values of historical walls measured in situ with the one calculated through literature data. In detail, the methodology includes a preliminary analysis of the historical envelope needed to carry out the in situ measurements of the thermal transmittance and an analysis of insulation material and its thickness to determine the optimal combination between the energy performance of the building and the investment cost for thermal insulation and environmental impact through the life-cycle cost analysis. After applying the methodology to a case study located in Italy, the results revealed that the exclusive use of literature data for the preparation of an energy recovery project for an existing historic building can lead to significant errors.

Deep renovation of historic buildings

Purpose 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. Design/methodology/approach Task 59 aims to achieve the lowest possible energy demand for historic buildings. This paper proposes a definition for this concept and identifies three key socio-technical barriers to achieving this goal: the decision-makers’ lack of engagement in the renovation of historic buildings, a lack of support during the design process and limited access to proven retrofit solutions. Two methods – dissemination of best-practice and guidelines – are discussed in this paper as critical approaches for addressing the first two barriers. Findings An assessment of existing databases indicates a lack of best-practice examples focused specifically on historic buildings and the need for tailored information describing these case studies. Similarly, an initial evaluation of guidelines highlighted the need for process-oriented guidance and its evaluation in practice. Originality/value This paper provides a novel definition of lowest possible energy demand for historic buildings that is broadly applicable in both practice and research. Both best-practices and guidelines are intended to be widely disseminated throughout the field.

Small-Scale Compressed Air Energy Storage Application for Renewable Energy Integration in a Listed Building

In the European Union (EU), where architectural heritage is significant, enhancing the energy performance of historical buildings is of great interest. Constraints such as the lack of space, especially within the historical centers and architectural peculiarities, make the application of technologies for renewable energy production and storage a challenging issue. This study presents a prototype system consisting of using the renewable energy from a photovoltaic (PV) array to compress air for a later expansion to produce electricity when needed. The PV-integrated small-scale compressed air energy storage system is designed to address the architectural constraints. It is located in the unoccupied basement of the building. An energy analysis was carried out for assessing the performance of the proposed system. The novelty of this study is to introduce experimental data of a CAES (compressed air energy storage) prototype that is suitable for dwelling applications as well as integration accounting for architectural constraints. The simulation, which was carried out for an average summer day, shows that the compression phase absorbs 32% of the PV energy excess in a vessel of 1.7 m3, and the expansion phase covers 21.9% of the dwelling energy demand. The electrical efficiency of a daily cycle is equal to 11.6%. If air is compressed at 225 bar instead of 30 bar, 96.0% of PV energy excess is stored in a volume of 0.25 m3, with a production of 1.273 kWh, which is 26.0% of the demand.

A review on Latvian Historical Building Stock with Heavy Walls

The conservation of historic buildings’ cultural values and the improvement of their energy performance can be perceived as rather contradictory. A thermal insulation cannot always be applied on the exterior surface of external walls. In that case, interior insulation measures should be investigated and currently represent the most difficult retrofit measure in historic buildings. The main objective of this study is to carry out literature review and to examine most commonly found historic building heavy wall types in Latvia, determine their physical properties, classify them by different types, observe and describe main historic building envelope deterioration symptoms and their possible causes. The study shows that historical buildings consume one third of total final heating energy consumed by both residential and non-residential building sector. The study also reveals that historical building external wall hygrothermal properties have not been widely studied in Latvia. This study will serve as basis for development of effective, comprehensive decision guidelines to improve the energy performance of historic buildings by investigating interior insulation measures.

The Attic and its Effect on the Energy Performance of Historic Buildings

This paper aims to investigate the problem of attics conservation or dismantling from historic buildings. The attic, unconsciously inherited and planned with the traditional building techniques, constitutes a precious architectural heritage in the field of historic housing in the whole European patrimony. In many cases, the peculiarities of the type of techniques and the use of traditional local materials are the reasons why attics constitute an evidence of an active culture of know-how that has to be preserved. Furthermore, the attic-mediated heat transfer between indoor and outdoor environments, contributes to the saving of building heat loss. Nevertheless, the practice of eliminating attics is particularly diffused, and building owner or architects, preferring to dismantle their structure, compensate this loss by using insulating boards to constitute the final roofing section.

Reprint of “Guidelines on energy efficiency of cultural heritage”

Summary The AiCARR Guidelines “Energy Efficiency in Historic Buildings” (February 2014) provide information to evaluate and improve the energy performance of historic buildings, fully respecting their significance and expression; where applicable these Guidelines will include the most recent legislation on the subject existing in Italy. These guidelines are intended for both design engineers and superintendencies. They provide the design engineers with a tool for the energy audit of the historic building and offer a framework for the design of possible energy upgrades, which are conceptually similar to that provided for non-protected buildings, but appropriately tailored to the needs and peculiarities of the cultural heritage. On the other hand, these Guidelines provide the institutions responsible for protecting the building, the possibility to objectively decide on the level of energy efficiency achieved as a result of the rehabilitation in accordance with the conservation criteria.

Guidelines on energy efficiency of cultural heritage

The AiCARR Guidelines “Energy Efficiency in Historic Buildings” (February 2014) provide information to evaluate and improve the energy performance of historic buildings, fully respecting their significance and expression; where applicable these Guidelines will include the most recent legislation on the subject existing in Italy. These guidelines are intended for both design engineers and superintendencies. They provide the design engineers with a tool for the energy audit of the historic building and offer a framework for the design of possible energy upgrades, which are conceptually similar to that provided for non-protected buildings, but appropriately tailored to the needs and peculiarities of the cultural heritage. On the other hand, these Guidelines provide the institutions responsible for protecting the building, the possibility to objectively decide on the level of energy efficiency achieved as a result of the rehabilitation in accordance with the conservation criteria.

Historic Buildings and Energy Efficiency

This paper aims to critically examine the issue of rendering historic buildings energy efficient. Although this subject has been discussed to some extent on the national and international levels, it largely has been under-theorised as the existing literature focuses mainly on technical matters related to the improvement of energy performance. Indeed, one of the main issues which has not been thoroughly addressed in the literature is balancing conservation needs on the one hand and improved energy performance of historic buildings on the other, partly due to improper analytical tools, methods, and parameters that are commonly used to classify the energy behaviour of historic buildings. It is the matter of insufficient existing tools which triggered the development of this paper. This paper is based on experimental measurements in order to determine the most relevant parameters and the average thermo-physical data of the historic building envelope. The experiments were followed by evaluation of the energy performance of three listed buildings in Italy using static (used for energy certification in Italy), semi- dynamic, and dynamic computer simulations, in order to understand which energy audit schemes best simulate the actual energy performance of historic buildings while identifying the strengths and limitations of each type of software. The simulations were carried out using experimental data on the thermo-physical parameters of the building envelope components, energy bills, temperature, and relative humidity of air. The ultimate goal was to define the appropriate intervention for ‘particular’ types of historic buildings, in order to optimise the energy-efficiency requirements along with preservation of their inherent cultural values.

The use of computerized energy simulations in assessing thermal comfort and energy performance of historic buildings

The balance between preservation objectives and the thermal needs of an historic structure is addressed in different publications that integrate the general recommendations of 'design with climate' with specific guidelines set forth by the US Secretary of Interior's Standards and Guidelines for Rehabilitation of Historic Buildings. These accepted recommendations serve as the basis for morphological qualitative analyses of thermal comfort of historic buildings. To augment these analyses, this paper introduces a systematic quantitative approach to determine the energy needs of these buildings and to develop energy conservation strategies in their retrofitting. Using a computerized energy simulation program the study proceeds in three major steps: (a) evaluation of the thermal comfort and energy performance of the target building in its original historic and its current conditions; (b) development of energy strategies to improve thermal conditions in the historic building, while maintaining the building's historic integrity; and (c) evaluation of these strategies. This paper demonstrates the utility of ENER-WIN - an hour by hour energy simulation program in testing thermal comfort and energy performance of three historic buildings: the 1868 St. Louis Catholic Church in Castroville, Texas, USA; Frank Lloyd Wright's 1905 Unity Temple in Oak Park, Illinois, USA; and a 1936 Bauhaus Apartment Building in Tel Aviv, Israel.