Performance-based parametric design explorations depend on formulating custom-designed workflows that require reading, writing, interpreting and manipulating databases, as part of the design process. The possibilities of customization and parameterization offered by the user-friendly interfaces of advanced building-performance simulation software and digital design tools have now enabled architects to carry out performance-based design explorations without the help of simulation experts. This paper presents a customized workflow methodology to explore design alternatives for producing shading devices that can optimize daylight, while blocking out excessive solar heat gains, in an office building in a hot and humid climate. The design alternatives were generated by evolutionary algorithms in accordance with daylight performance requirements and simulated to assess their shading and daylight efficiencies. (C) 2015 Elsevier Ltd. All rights reserved.