Acoustic retrofit strategies of windows in facades of residential buildings: Requirements and recommendations to reduce exposure to environmental noise

Abstract

Achieving an adequate indoor acoustic comfort environment is one of the main priorities to avoid adverse effects caused by noise. Façades are the constructive elements most likely to be retrofitted due to their delimiting function between indoor and outdoor space. This study compares the acoustic façade requirements established for new and existing buildings in current national building regulations. The assessment of regulations and the analysis of a comparison model, examining different techniques for improving sound insulation, conclude that on a global scale there is a lack of consensus on external noise insulation and acoustic requirements worldwide. It is not possible to merely summarize all requirements into a single number as the sound insulation required depends on the performance of the building element, the outdoor noise level or the indoor noise level. Therefore, there is an in-depth discussion on the harmonization of external sound insulation requirements in acoustic regulations. This study also analyses façade wall solutions of existing housing stock and compliance with current regulations, with results showing that upgrading interventions focused on windows can be sufficient to propose suitable constructive systems in compliance with requirements established worldwide when external noise amounts to 60 dB(A) measured 2 m from the façade.