Cost for implementation of acoustic performance levels of NBR 15575 in vertical fence systems

Abstract

Overall, the performance of Brazilian residential buildings reached a new pattern since the implementation, in 2013, of the Brazilian construction standard ABNT NBR 15575, also known as “Performance Standard”. This standard requires several building components to meet a mandatory minimum performance level, or intermediary or high, if desired. One of these components is wall framing (both external and internal). This particular study analyzed an architectural plan of a residential building, assembling different wall framings that are able to fully meet the three acoustic performance levels of the related standard. The cost comparison was made between these acoustic levels on all external and internal walls and among different materials (bricks and drywall) on internal walls. The results show the approximate cost increase in adopting intermediary or superior acoustic performance in walls is at, respectively, 11% and 22%, when compared to the cost of building walls that only meet the minimum performance level. These increases occur mostly due to the considerable influence that aluminum windows and wood doors present to the walls themselves, because their (windows and doors) costs are significantly higher according to their acoustic performances.