Impact of the transparent building envelope in energy performance: numerical relation between shading coefficient and energy consumption in high-rise buildings in Santiago, Chile, as calculated by building performance simulation study cases.
The construction of high-rise buildings has been globally increasing for years, as a response to densification, social needs and economic growth around world. In Santiago, Chile, said buildings can rise from twenty stories up to 50 stories high, accommodating hundreds of people in their working or living spaces. The environmental impact of these buildings is therefore, much greater than a single story or a low-rise construction -whilst having the same land use- making energy efficiency and sustainability important aspects of analysis. In this context, one of the most relevant aspects of architectural design in high-rise buildings is the composition of the transparent building envelope.
The morphology of high-rise buildings makes the vertical facades a key element of study, because it accounts for most of its thermal gains and losses, due to higher surface dimensions. This is particularly important in building typologies that have high internal loads, hence creating considerable thermal “gains” that create poor thermal comfort conditions and greater HVAC costs. Therefore, the quality of the transparent building envelope -specifically thermal transmittance and shading coefficient- will be critical to provide optimal comfort and lower energy use. The relationship between shading coefficient reduction (or increase) of the transparent building envelope and the energy consumption, can be thus quantified and a measured in numerical terms.
Keywords: Glazing, Thermal Comfort, Solar Factor, Shading Coefficient, Thermal Transmittance, Energy Consumption, Transparent Building Envelope.