Climate Based Daylight Modelling (CBDM) is achieved with the LiVi CBDM node. CBDM takes hourly sky data, in this case from an EPW weather file selected in a VI Location node, and calculates lighting metrics either cumulative;y for the period simulated, or for each hour. CBDM offers greater contextualisation compared to a daylight factor calculation, and greater confidence compared to static time based simulations. A typical node set-up for a LiVi CBDM analysis is shown below.

CBDM analysis for the calculation of advanced lighting metrics such as light exposure (luxhours), radiation exposure (kWh/m²), daylight availability (%), hourly radiation (W), and useful daylight illuminance (%).

A short video showing a CBDM analysis can be watched below.

VI-Suite Climate Based Daylight Modelling from Ryan Southall on Vimeo.