Regulations and certification systems on Daylighting performance metrics in workspaces
Entrena-Martínez, I.(1), Castillo-Martínez, A.(2), Peña-García, A.(1) 1. Department of Civil Engineering. University of Granada, Granada, Spain 2. Department of Mechanical and Mining Engineering, University of Jaén, Linares, Spain 2026-06-27

Abstract

This study examines the inconsistencies between scientific advances in daylight metrics and their implementation in the regulations and certification standards governing workplace design. Over the last decades, climate-based daylight metrics (CBDMs) have become prevalent in research, since this measure provides a more realistic representation of annual daylight variations. Added to CBDMs, novel metrics including perceptual metrics and indicators of the non-visual effects of daylight have been developed. However, the implementation of advanced metrics in building regulations and standards is still limited and inconsistent with advanced approaches. A structured comparative study was conducted to assess the alignment of lighting regulations and certification standards with scientific evidence. Our analysis was focused on the type, temporal dimension and role of metrics in laws, standards and certification standards. Our results demonstrate a structural mismatch: whereas dynamic, perceptual and circadian metrics are increasingly used in studies, their implementation in regulations and standards is still limited. Certification standards serve as a stepping stone to the incorporation of advanced metrics into regulations.  We need to advance towards a more consistent and integrative use of daylight performance metrics combining the visual, perceptual and physiological dimensions of natural light to align building regulations and design practice with scientific knowledge.

Key words: Daylight metrics, climate-based daylighting, workspaces, building lighting standards, building certification systems.

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