Shading and layout influence on flats energy performance of an apartment building

Iole Nardi,Marialisa Sarcina

doi:10.1051/e3sconf/202019702013

Abstract

Giving the need for environment protection and energy need reduction, especially in the building sector, it is important to clearly understand what influences, and to what extent, buildings’ energy performance. In this work, an apartment building has been considered, and the influence of shadings and of flats layout on the energy performance ratings are evaluated. The case study is a building of the ‘90s, which has been demolished and re-built (2016) according to the actual energy requirements. For each of the 16 flats of the building, the energy certificate has been retrieved in the two configurations: before and after reconstruction. From the analysis of the specific energy consumption, and of their components (i.e. energy need for ventilation, transmission losses, solar gains), in the two configurations, a comparison amongst the flats has been drawn. Results show that the apartment layout influences the solar gains, but this influence (in percentage) is higher in the “ex-ante” configuration than in the “ex-post”. Similarly, the energy gains are more relevant in the “expost” configuration, in which some apartments, although having higher dispersing surface, result to be more efficient due to their favourable exposition.

Highlights

The growing attention to building energy consumption and related environmental impact has led to the increasing spread of knowledge concerning these two aspects
This datum is meaningless when not paired with the total energy consumption of the building itself [11]
Results are shown in Fig.7. where it is evident that before reconstruction transmission losses were high for all the apartments, and orders of magnitudes higher than the solar gains

Summary

Introduction

The growing attention to building energy consumption and related environmental impact has led to the increasing spread of knowledge concerning these two aspects. This datum is meaningless when not paired with the total energy consumption of the building itself [11] In this paper, such point is focused, demonstrating that, according to the Italian building energy evaluation methodology, a better energy label does not directly imply a higher energy efficiency. To this aim, an apartment building has been considered. The energy certificate of the 16 flats of the building has been evaluated, both before and after the reconstruction, according to the technical standards in law in 2016 This way has been chosen to highlight the differences of the energy consumption and the modification on the energy label and on the possible “ranking” of the flats. The differences have been studied in light of considerations on the solar gains and on the transmission losses of each apartment, according to its exposure, evaluating the effect of the surrounding buildings and of the solar path

The case study

Evaluation method

Results and discussion

Conclusions