Hospital Facade Renovation for Improved Daylight Performance: A Case Study of BIHS General Hospital, Mirpur, Dhaka, Bangladesh

Abstract

Rapid urban growth in Dhaka has placed increasing pressure on older healthcare buildings, many of which struggle to provide adequate daylight, comfort, and environmental quality. Poor façade design often limits access to natural light, increases dependence on artificial lighting, and reduces user satisfaction. This study examines the renovation of the west façade of BIHS General Hospital in Mirpur, Dhaka, with the aim of improving daylight availability, visual comfort, and overall user experience. Existing daylight conditions were assessed through on-site illuminance measurements using a mobile lux meter and digital simulations conducted with the Enscape plugin. The original solid façade significantly restricted daylight penetration and produced illuminance levels below recommended standards. A redesigned louvred façade system was proposed to allow controlled daylight entry while minimizing glare and heat gain. Post-renovation simulations showed a noticeable improvement in daylight distribution within consultation rooms and staff cabins, bringing illuminance levels closer to accepted benchmarks. The findings demonstrate that thoughtful façade retrofitting can meaningfully enhance indoor environmental quality, reduce energy demand for artificial lighting, and improve user satisfaction in aging hospital buildings. The study offers practical insight for sustainable renovation strategies in dense urban contexts similar to Dhaka.