Partial interventions on the facades in the process of energy renovation of residential buildings - examples from the Serbian construction practice

Abstract

Energy rehabilitation of facades of residential buildings is a process aiming to improve housing comfort and save operational energy. In the case of multi-family housing in Serbia, this procedure often involves partial interventions on the facade, which are mainly due to limited investments and lack of consensus at the building level to implement a comprehensive rehabilitation process. There are currently several approaches, such as: 1) replacement of facade joinery as a measure taken by tenants most often individually, without synchronization at the building level; 2) thermal insulation of the facade as a technologically more complex measure in which, in certain cases, due to the lack of agreement between all users of the building, certain façade zones remain uninsulated; 3) in rare cases, repair of leaking of flat roofs, with integrated complete or partial thermal insulation. The paper analyses several situations arising as a result of partial interventions for which, in accordance with EN 10211, a numerical simulation was performed using the T-Studio software. It has been found that the problems caused by a partial insulation of the facade or a partial replacement of facade joinery lead to the occurrence of thermal bridges and increase of the heat flow in certain areas of structures with a reduction in internal contact temperature, which increases the risk of condensation, with consequences in the form of development of mould and of microorganisms, which leads to reduction of life comfort and possible specific diseases of the user. Such negative phenomena occur both, in the apartments whose owners did not participate in the process of energy rehabilitation of facades, and in the contact zones of energy rehabilitated apartments, which, in this way, lose their invested assets and the expected effects of energy savings.