Architect and Builder July/August 2015 | Page 114

QUALITY CLASSROOM ENVIRONMENT AT THE CHIEF ALBERT LUTHULI PRIMARY SCHOOL Today, and thanks to a decade of empirical research and analysis of real buildings under real world conditions at the University of Newcastle, Priority Research Centre for Energy, various parametric studies and no less than five thermal modelling studies of different building typologies comprising different wall construction types, the clay brick industry has clear evidence that wall construction types that include clay brick will outperform comparable lightweight walled buildings in South African climates. The thermal mass inherent in clay bricks is what brings the ‘X’ factor to the thermal efficiency equation. While research confirms insulation in the walls is an important contributor for achieving energy efficiency in 40m² and 130m² house types in the colder winter climate zones where insulated cavity brick is the top performer, the research has dispelled the notion that the wall R-value is the all-important thermal performance property. As shown in Table 1, when it comes to office/institutional type buildings solid 220mm double skin clay brick walls (R0.45) and 270mm clay brick cavity walls (R0.65) provide requisite thermal mass and resistance to outperform SANS 204 compliant lightweight walling (R1.9 and R2.2) in terms of day-time thermal efficiency. The University of Pretoria study produced some key findings that included: 1. “Solid clay brick masonry is the most thermally and energy efficient walling system considered for day-time or nonresidential occupancy buildings” 2. “Clay brick masonry cavity walls are the most thermally and energy efficient walling system considered for all day or residential occupancy buildings” 3. “Light steel frame wall construction specified in SANS 517 is not thermally efficient and uses more heating and cooling energy compared to clay brick masonry cavity walls in all climatic regions”, An important further finding of the University of Pretoria study, that has a correlation with the findings of the empirical research at the University of Newcastle, is that clay brick internal partition walls enhance energy efficiency of buildings no matter the external wall construction type. LFF SCHOOL EASTERN CAPE – WALL PANEL SEPARATION AND SHABBY INTERNAL COMMUNAL SPACE 12 Clay Brick