A rigorous, climate-data-driven method for analysing building facades and engineering external solar shading that controls heat gain, glare and overheating across South African orientations.
Most overheating disputes on South African buildings trace back to a facade that was never analysed orientation by orientation. This masterclass gives registered architects and engineers a rigorous, climate-data-driven method to read the sun-path, derive shadow angles, characterise glazing, quantify solar gain, and engineer external shading that controls heat, glare and overheating across every SA orientation — defensibly, and within the SANS compliance framework.
Sun angles describe where the sun is; shadow angles describe what a device must do. This lecture introduces the two angles that translate solar geometry directly into device geometry: the Horizontal Shadow Angle (HSA) and the Vertical Shadow Angle (VSA). You will learn to compute VSA for horizontal overhangs and HSA for vertical fins from the solar altitude and the wall-solar azimuth, and to use the shadow-angle protractor overlaid on a sun-path chart to design a device that shades a window across a chosen period. We size a north-facade overhang for a Bloemfontein office so it fully shades at the summer solstice noon yet admits winter sun, demonstrating the seasonal selectivity that good shading exploits. By the end you can convert any required shading period into the precise overhang depth or fin spacing that delivers it.
The shadow-angle method is the bridge between astronomy and construction detail, and mastering it is what separates a specifier who guesses overhang depths from one who engineers them. Two angles do all the work. The Vertical Shadow Angle (VSA), sometimes called the profile angle, is the angle of the sun's projection onto a vertical plane perpendicular to the window — it governs horizontal devices (overhangs, light shelves, horizontal louvre blades). It relates to solar altitude (alt) and the wall-solar azimuth (gamma, the horizontal angle between the sun's azimuth and the facade's outward normal) by tan(VSA) = tan(alt) / cos(gamma). The Horizontal Shadow Angle (HSA) is simply the wall-solar azimuth itself, HSA = solar azimuth - wall azimuth, and it governs vertical devices (fins, vertical louvres).
A north window 1.8 m tall, summer-noon VSA ~80°: P = h / tan(VSA) = 1.8 / tan(80°) = 0.32 m. A 320 mm overhang fully shades summer sun, yet winter sun (VSA ~35°) penetrates 0.22 m — free seasonal selectivity.
Target audience: South African registered architects (SACAP), professional engineers (ECSA), interior design professionals (IID) and facade/shading specifiers undertaking commercial and institutional building work.
Assessment: 10 application-based multiple-choice questions, minimum pass mark 70%. Certificate of completion on passing.
Your enrolment includes the full C18 package: the in-depth eBook, the practical how-to guide with the full assessment bank, and the A4 quick-reference cheat sheet.