Analysis of Air Permeability of Insulated Masonry Walls

Abstract

Recently, the construction of external ventilated walls has become popular for public and office buildings. These blocks are used without internal rendering because of their good interior surface, stable dimensions and various filling of masonry joints, which provide an attractive architectural appearance. However, problems with the airtightness of such walls often occur. Currently, there are no standard methods to predict the airtightness of such wall. In practice, samples of particular walls are produced, and their air permeability is measured at laboratories. For the broader use of the results of laboratory air permeability measurements, a methodology has been developed to predict the air permeability of block masonry walls using experimentally determined air flow resistances of the individual layers. The masonry from various blocks were used for the research; mineral wool boards of various air permeability were used for thermal insulation and the wind protection layer. After measuring the air resistance of the samples, the air flow resistances of walls of different construction were calculated. This study compared the calculated and measured air permeability values of different wall masonry samples and evaluated the suitability of created calculation method for prediction of the airtightness of insulated block masonry wall.

Keywords

• building envelope airtightness
• air permeability
• air resistance