• Energy Research

Abstract Lack of information and transparency increases risk and undermines investor confidence. Therefore, a systematized and optimized capture and processing of information also supports investment decision making and creates opportunities for innovation and uptake of energy efficiency and sustainability measures, processes and designs. Building passports could play a valuable role in boosting the availability of information to a wide range of market participants. Better information flows are a necessary part of improving the quality assurance system for buildings and the construction industry market overall. The aim of the paper is firstly to set a Building Renovation Passport (BRP) definition, to explore the potential role of a voluntary scheme across EU as a key tool to help overcome this information imbalance by providing all market stakeholders, including financing institutions, providers of mortgage credit, investors and insurers with access to key building related documentation and information to properly assess the many factors impacting the overall quality of buildings. Within the presented study three initiatives currently developed across EU (Flanders, France and Germany), have been selected to be investigated in details providing an extensive overview of the process supporting the creation of a Building Renovation Passport and covering the main issues necessary for its development and implementation.

Abstract The environmental concern in light of anthropogenic climate change is directly concerning the building sector as one of the major energy consumers and CO2 producers. To reduce the environmental impact of new and refurbished buildings, one of the most promising policies is the widespread adoption of Building Energy Regulation Codes (BERC), since they have a direct impact on the everyday work of local planners, architects, engineers and building companies. This article will look at how BERCs were implemented in Italy, where Regions and municipalities have developed in recent years a number of local regulations trying to drive the market towards more energy efficient practices. This happened in a legislative vacuum because the Italian Government implemented the European Directive on the Energy Performance of Buildings (2002/91/EC) only in 2005 and defined the related National Guidelines only in 2009. This article provides an overview on EPBD implementation in Europe and a Geocluster Italian distribution of BERCs in order to show their geographical distribution and their influence on the construction sector practices, focusing in particular on the region of Lombardy. Then the article describes the methodology followed for the definition of BERCs in nine municipalities in the same region. In conclusion, the paper presents the practical application of one of the nine BERCs to a NZEB residential case study as an example of what the EBPD recast define as nZEB.

Abstract Politecnico di Milano (POLIMI) has launched since 2011 the project “Citta Studi Sustainable Campus” to improve the university’s sustainability performances within three main principles: building refurbishment, sustainable campus development and integration of facilities, research and education. The paper aims to discuss these issues, focusing on the energy efficient refurbishment on two university campuses in Milan, Italy. A Methodology for Energy Efficient Building Refurbishment (MEEBR) has been identified and tested on two case studies with students of the Integrated Design Refurbishment Laboratory of Building Engineering Faculty at POLIMI. In particular, the performance energy analyses were conducted on two university building case: the first at POLIMI campus, and the second located in the Universita degli Studi di Milano (UNIMI) campus. These analyses were carried out using numerical simulations, considering the increasing important role which software are playing in refurbishment building design process also in early design phase. This preliminary experience with students on MEEBR application, with also the overview on building refurbishment methodologies, show that case study examples can help to: increase consideration of the integrated research approach and improve sustainability performance in historical buildings taking into account also the user’s participation of a university campus. The comparison of the energy assessment methodology, of the two software used for the analyses (CENED+ and Sefaira), leads to the statement that it is essential from the beginning, selecting a program in function of the particular job and the outputs that you want to reach with the tool.

Abstract The recast Directive on the energy performance of buildings (EPBD) stipulates that by 2020 all new buildings constructed within the European Union after 2020 should reach nearly zero-energy levels. This means that in less than one decade, all new buildings will demonstrate very high energy performance and their reduced or very low energy needs will be significantly covered by renewable energy sources. Such change is affecting both the nature of the built environment as well the actual method of designing and constructing a facility. The economic feasibility to realize a sustainable construction need to have a clear support by adequate analyses connected to the energy consumption and consequently to the new target reductions in greenhouse gas emissions for buildings. Life Cycle Methodologies (LCMs) are currently not considered in details on the EPBD recast, but according also to recent researches, they might be important tasks in a future recast. The paper analyses this challenge providing an overview on the main LCMs to individuate principles, limitations and implications of these approaches to design a Nearly Zero Energy Building (nZEB).

The recently developed TAIL rating scheme enables assessment of the changes in the indoor environmen- tal quality (IEQ) associated with a building’s deep energy renovation (DER) and classification of the resulting quality levels of the thermal (T), acoustic (A), and luminous (visual) (L) environments and indoor air quality (I). Since the TAIL rating is primarily based on measurements, it cannot be determined prior to renovation operations to help design the IEQ. To fill this gap, the PredicTAIL method was devel- oped in the present study to predict the changes in ten of the twelve TAIL parameters as a result of DER. These parameters are indoor air temperature, relative humidity, sound pressure level, daylight factor, illuminance, and concentrations of carbon dioxide, formaldehyde, benzene, radon, and PM2.5; no predic- tion is made for ventilation rate or mold. To examine the feasibility of the PredicTAIL method and the sen- sitivity of the existing models for quantifying changes in the TAIL parameters corresponding to different renovation strategies, simulations were performed in a hotel and an office building using TRNSYS, IDA ICE, ACOUBAT, MATHIS-QAI, and PHANIE. These modeling tools were first benchmarked against the TAIL parameters measured in the buildings before renovation. Once the agreement between measure- ments and modeling was considered acceptable, four pragmatic renovation scenarios were applied, and their impact on the IEQ parameters was quantitatively modeled. The simulations showed that the quality levels of the IEQ parameters were improved or unchanged for some parameters but degraded for other parameters after DER. The changes in the IEQ parameters and the TAIL rating depended on the renovation scenarios, suggesting that the PredicTAIL method is sufficiently sensitive to guide renovation design.

Energy retrofit strategies for buildings represent a major challenge for the achievement of EU decarbonization goals. In 2002, the Energy Performance of Building Directive introduced energy certificates to measure and compare building energy performance, to frame the more suitable renovation actions, and develop financing schemes. However, since its implementation, this instrument remained quite unexploited. In this framework, the EPC RECAST H2020 project aims at developing a new generation of EPCs with a focus on existing residential buildings. Within the project, the paper focuses on the monitoring strategy that has been defined and tested to validate, with real data, what is declared in Energy Performance Certificates.

Extensive green roofs are considered an effective energy conservation measure for increasing buildings’ energy efficiency and reducing the heat wave effect in dense build environments. In this context the present work has a two-fold objective: the first is to test and analyse a commercial extensive lightweight green roof sample through an experimental monitoring campaign carried out in a hot climate during the summer time; the second is to provide a practical case study application showing the architectural integration of the extensive green roof technology for existing buildings. The experimental monitoring campaign has been set for analyzing the temperature levels of an extensive green roof compared with a traditional horizontal roof finished with cement tile. The temperature levels have been analysed through a set of sensors positioned at different levels to characterise the green roof response to the climatic forces during summer. The results show that the air temperature in proximity to the green surface (15 cm above the greenery) is warmer than the undisturbed ambient air temperature during the day and lower during the night by 2–2.5 ◦C. The soil substrate and the vegetative layer contribute to increase ambient air humidity levels. As expected, the evapotranspiration of the green layer increases during a typical sunny day resulting in more water content in the air above the vegetative level of about 4–8 %. The surface temperature of the ground below the vegetation layer and the temperature of the ground layer (8 cm deep) shows beneficial attenuation and time shift properties with respectively 12–15 ◦C and 3–4 h. Compared to the traditional cement tiles the green roof shows lower intralayer temperature with differences ranging from 6 to 8 ◦C. Moreover, the renovation case study represents a practical example of green roof technology integration in a real environment. The study has high replicability, and it is meant to be an interesting example for researchers and professionals to boost the green roof technology application for higher-quality built environments.

Abstract To avoid health risks and discomfort, the European Energy Performance for Building Directive (EPBD) mandates that “Member States should support energy performance upgrades of existing buildings that contribute to achieving a healthy indoor environment.” There is, however, no widely accepted method for rating the overall level of indoor environmental quality (IEQ), although several different approaches are proposed by standards, guidelines, and certification schemes. To fill this void, a new classification rating scheme called TAIL was developed to rate IEQ in offices and hotels undergoing deep energy renovation during their normal use; the scheme is a part of the energy certification method developed by the EU ALDREN project. The TAIL scheme standardizes rating of the quality of the thermal (T) environment, acoustic (A) environment, indoor air (I), and luminous (L) environment, and by using these ratings, it provides a rating of the overall level of IEQ. Twelve parameters are rated by measurements, modelling, and observation to provide the input to the overall rating of IEQ. Their quality levels are determined primarily using Standard EN-16798-1 and World Health Organization (WHO) air quality guidelines and are expressed by colours and Roman numerals to improve communication. The TAIL rating was shown to discriminate IEQ levels when its feasibility was examined in eleven buildings across Europe to provide support for its applicability and input for further modifications. Opportunities for using the scheme in other types of buildings and for its further development and application are discussed.