Acoustic analysis of facades of light steel framing and flat sheets

Abstract

Dry construction has been considered as a technological alternative to conventional construction systems, and in recent years, systems as Light Steel Frame and Drywall have been used on a larger scale in Brazil. These systems consist of structured panels by steel profiles, filled internally by an insulation wool and sealed with flat plates on internal and external faces. It was verified that, in Brazil, the most used slabs in the external closure of these panels are produced from Portland cement and fibers, and there are therefore commonly referred how fiber cement. In the China and the US, they have alternatives such as plates made with magnesium oxide, called flat magnesium plates, whose application has been incipient by the Brazilian work construction. The performance standardization for popular residential (NBR 15.575), it was proposed an acoustic analysis of these panels from a special prototype, adopting as variable the plane flat. The differences in air sound insulation evaluated from the measurement of the parameter D2m, nT as a function of frequency according to ISO 140-5 and the calculation of the parameter D2m, nT, w (ISO 717-1) were studied, having as criterion the NBR 15575-4. The results presented in this work demonstrated that the magnesium based flat plates can collaborate for a better sound insulation throughout the frequency range, with a gain of 4dB in the insulation compared to conventional fiber cement panels.