Traditionally, the analysis of daylight has focused on the adequacy of illumination under static, overcast (diffuse) sky conditions; the most commonly used metric being the daylight factor (DF%). Whilst this may be a relevant method of analysing the worst case conditions in temperate climates, as commonly found during winter months within the UK, it provides little useful information regarding the expected illuminance levels at other times i.e. partly cloudy or clear sky conditions and thus limits the understanding of the annual illuminance profile within interiors, visual comfort (glare) and potential energy savings.
Climate-Based Daylight Modelling (CBDM) refers to the simulation of annual daylight profiles within architecture, using 3D computer models in conjunction with specialist lighting simulation software and measured climate weather files for the site location.
Lighting Analysts have been pioneering the use of these dynamic simulation methods for over a decade, enabling a better understanding of the annual daylight illuminance profile within buildings, ensuring optimal design of the building is achieved and that maximum energy savings are made through the use of daylight-linked lighting controls.
CBDM also enables the annual cumulative exposure (kilolux/hours) to be analysed in spaces such as museums and art galleries, which is essential to their conservation - artefacts that are sensitive to light have set exposure limits which is dependent on their material composition.