128 research outputs found
Energy Retrofit Strategies for Residential Building Envelopes: An Italian Case Study of an Early-50s Building
During the last few years, the issues of energy efficiency and energy saving have dominated the buildings research field. New constructions are based on efficient design and, because of this, the real challenge is to retrofit existing buildings. Italian standards impose thermal transmittance limits for opaque and transparent surfaces, according to the climatic area. In order to understand buildings' energy behavior, an accurate analysis, carried out by employing advanced calculation codes and instrumental diagnosis—provided by the use of heat flow meter, surface temperature probes and thermal imaging camera—is needed. In this paper, a structure built in the 50 s has been analyzed, by means of a measurement campaign, to investigate the building's characteristics and its vulnerability. Finally, some retrofit hypotheses have been evaluated by means of a well-known dynamic code. All investments have to be analyzed under a financial point of view, considering materials and installation costs. For this reason, the payback time has been calculated in order to understand how quickly the energy upgrading can be repaid
Influence of insulating materials on green building rating system results
This paper analyzes the impact of a change in the thermal insulating material on both the energy and environmental performance of a building, evaluated through two different green building assessment methods: Leadership in Energy and Environmental Design (LEED) and Istituto per l'innovazione e Trasparenza degli Appalti e la CompatibilitĂ Ambientale (ITACA). LEED is one of the most qualified rating systems at an international level; it assesses building sustainability thanks to a point-based system where credits are divided into six different categories. One of these is fully related to building materials. The ITACA procedure derives from the international evaluation system Sustainable Building Tool (SBTool), modified according to the Italian context. In the region of Umbria, ITACA certification is composed of 20 technical sheets, which are classified into five macro-areas. The analysis was developed on a residential building located in the central Italy. It was built taking into account the principles of sustainability as far as both structural and technical solutions are concerned. In order to evaluate the influence of thermal insulating material, different configurations of the envelope were considered, replacing the original material (glass wool) with a synthetic one (expanded polystyrene, EPS) and two natural materials (wood fiber and kenaf). The study aims to highlight how the materials characteristics can affect building energy and environmental performance and to point out the different approaches of the analyzed protocols
Influence of soundscape in the experience of an urban area: a case study in Rome
Over the last years several studies have demonstrated how the same environment can lead to different perceptual outcomes if the surrounding sounds change. Soundscape studies promote a user-centred approach for the characterization and management of acoustic environments in cities. There are several available protocols to gather perceptual data about how people experience the soundscapes in urban areas, and the most common tool is the “soundwalk”, a procedure where a group of people walks and stops at given locations in order to assess the acoustic environment, using some sound-related attributes (e.g., calm, pleasant, vibrant, chaotic, etc.). This research aims at evaluating the influence that different acoustic conditions together with specific environmental ones can induce on the pedestrians’ perception. In particular, the analysis was carried out within an artistically significant and culturally relevant urban district characterized by different traffic conditions, such as the archaeological area of the Colosseum in Rome. For this purpose, a soundwalk combined with a sound levels measurement campaign was organised in the archaeological area outside the Colosseum, during daytime and night time conditions, with a group of students applying the Method A of the ISO/TS 12913-2:2018, which addresses soundscape data collection. The results show how the correlations between the subjective responses and the measured data are significant and they can vary if the surrounding changes, both in terms of acoustical characteristics and environmental ones
A New Method of Technical Analysis to Optimise the Design of Low Impact Energy Systems for Buildings
Energy consumption for civil constructions represents about 40% of total energy requirements, so it is necessary to achieve the goal of energy savings and the consequent reduction of greenhouse gases emissions. The study in content aims to provide a design methodology enables to identify the best plant configuration for buildings from a technical, economic and environmental point of view. To assess validity of the calculation model, an analysis of an historical building was carried out in combination with two softwares of proven reliability: TRNSYS, used to evaluate the thermal demand of users, and RETScreen, used to estimate the validity of the chosen energy model
Experimental Evaluation and Numerical Simulation of the Thermal Performance of a Green Roof
In the building sector, both passive and active systems are essential for achieving a high-energy performance. Considering passive solutions, green roofs represent a sustainable answer, allowing buildings to reach energy savings, and also reducing the collateral effect of the Urban Heat Island (UHI) phenomenon. In this study, a roof-lawn system was investigated by means of an extended measurement campaign, monitoring the heat transfer across the roof. Heat-flow meters and air- and surface-temperature probes were applied in a real building, in order to compare the performance of the roof-lawn system with a conventional roof. This experimental approach was followed to quantify the different thermal behaviors of the building components. Moreover, an equivalent thermal model of the roof-lawn system was studied, in order to obtain the equivalent thermal properties of the roof, useful for setting building models for yearly energy simulations. The roof-lawn system revealed its advantages, showing a higher thermal inertia with no overheating in summertime and a lower thermal transmittance with energy savings in wintertime, and, consequently, better indoor conditions for the occupants of the building
Neighbourhood sustainability: State of the art, critical review and space-temporal analysis
This paper introduces a review on sustainability-related concepts at a neighbourhood scale. 3909 abstracts of papers on “neighbourhood sustainability” published between the late eighties and February 2020 were downloaded from Scopus in order to perform a text mining analysis. The concept of neighbourhood sustainability is studied and discussed at both geographical and temporal level, employing clustering methods. Marked differences in the elaboration of neighbourhood sustainability-related concepts can be tracked at spatial level and linked to the different socioeconomic, cultural and climatic conditions of the considered geographic areas. A significant temporal evolution of the concept can be also tracked with a focus on specific aspects of the sustainability concept in different periods of time. The analysis can help in defining more rigorous evaluation categories and criteria for neighbourhoods sustainability rating systems: new criteria should be included and an international homogenization is recommended in the definition of a common scheme of macro-categories, as well as local versions of the tools. Finally, the adoption of a dynamic approach, that doesn’t stop after the projects realization, is proposed for the evaluation of the sustainability at a neighbourhood scale
- …