1.4.5 Integrated Solar Shading
Reduce solar heat gain by using solar shades integrated between panels of an Insulated Glazing Unit (IGU) which can be fixed or adjustable.
Insulated glass units (IGUs) may contain fixed louvers, metal screens, or PV-film that optically control light and heat transmission (i.e. Seattle Main Library). Triple IGUs with an integrated metal mesh provide access to views and reduce solar gain (i.e. Des Moines Library). Double skin facades provide two layers of individually framed glass units separated by a significant amount of air space. This allows for accessible cavity-induced stack ventilation, integrated solar, thermal and acoustic performance.
Shading devices reflect direct solar radiation, preventing UV radiation from entering the building, thereby limiting infrared radiation on surfaces. Solar radiation gain through the glazing can be reduced by up to 80 percent. Use design simulation software for sun path diagram and shading model analysis to optimize the geometry.
Estimated energy savings can be up to 35 percent.
Maximum ability to reduce solar heat gain, control quality of light and minimize operational energy cost. Encapsulated assembly allows for protection from the elements, controlled maintenance from inside, ease of exterior window washing, and uncompromised envelope design potential.
Cost-benefit considerations usually lead to applications on larger projects, due to the economy of scale. More energy-efficient than interior blinds. Lower maintenance than interior or exterior blinds but replacement units can be costly.
5.1.3 Daylight Modeling