Computational method for variable objectives and context aware solar envelopes generation

Daylight requirements are an important factor for the layout and image of cities. In Estonia complex requirements of direct solar access guarantee the right-to-light for existing and new housing buildings. Nowadays different environmental design software permits to calculate the quantity of direct sunlight hours for facades or windows and allows designers to generate solar envelopes. This is an efficient method to calculate the shape of the maximum buildable mass on a plot that allows the neighboring buildings to receive a required amount of direct sunlight. The existing method to generate solar envelopes presents a significant limitation when applied to the Estonian daylight standard. The present work discusses a method that consider specific amounts of direct solar access and take the context into account to improve the actual solar envelope generation method and available tools. The tests carried out in four different urban areas show that the proposed method is superior to the existing. It generates significantly larger size solar envelopes that fulfill the requirements with a small margin of error. The outcomes can be generalized to underline the importance to consider the requirements of specific facades when calculating solar envelopes in urban environments and the incidence of the context layout.