Thermal and acoustical performance of building systems: study of tools that assist NBR15,575/2013 Brazilian building standard compliance assessment

ABSTRACT The Brazilian performance building code (NBR 15,575) addresses some requirements to assess the residential sector. However, setting a construction system option that meets this code has proven to be challenging. This study aims to evaluate the thermal and the acoustic performance of a social housing envelope, situated in Contagem-MG (Brazil), according to the minimal limits set by NBR 15,575. Structural masonry of ceramic blocks was selected for vertical sealing as well as concrete (floor-pavement) slab and ceramic tile, for horizontal closure. The NBR 15,575 simplified method was carried out for thermal analyzes whereas acoustic evaluation applied standard calculation and simulation method using Projetus software. Results indicated that the external walls need a thermal capacity improvement and the living room inner wall, which splits both unit apartments, need to increase its sound reduction index (Rw). Therefore, 2.5cm of plaster in both sides of wall should solve those problems. After this change proposition, the thermal and acoustic minimal performance standard were achieved. A small variation could be notice between calculation (Rw) and simulation sound insulation results (DnT,w and D2m,nT,w). Projetus is perfectly suitable for preliminary studies. As a conclusion, thermal and acoustic building system assessment in an early stage show to be relevant to foster its compliances adjustments as occurred e.g. in this study. Otherwise, major interventions may be necessary either at building site or after construction ends.