Belfast·SPG006 Tall Buildings·Page 27·5.7.2
Sunlight, daylight and overshadowing assessment
Environmental quality impacts from tall buildings including loss of sunlight and daylight and overshadowing of public and private spaces must be assessed. Sunlight/daylight and shadow analysis studies demonstrating existing versus proposed scenarios are required, with emphasis on equinoxes (21 March and 21 September) as baselines, using a more slender north-south oriented building footprint where feasible.
Environmental quality can be adversely impacted by tall buildings through the loss of sunlight and/or daylight and the overshadowing of public and private amenity space, streets, civic spaces and parks. In this regard, consideration may need to be given to pursuing a more slender building footprint for the taller component that maximises a north-south orientation so as to limit the extent of overshadowing. Sunlight/daylight and shadow analysis studies should form part of the TBDS with emphasis placed on both equinoxes as baselines (March 21 and September 21), demonstrating the existing scenario against that resulting from the tall building. Depending on the type of adjacent uses and their sensitivity to loss of sunlight/daylight and overshadowing, further assessment of other dates and times of the year may be required.
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