Kericho Cathedral, a unique place of worship in the Highlands of Kenya designed by John McAslan + Partners, is a synergy of lighting with architecture. Characterised by the strikingly inclined roof and ascending interior volume, natural lighting plays a fundamental role for its symbolic significance to the Catholic faith.
Arup’s comprehensive lighting design service combined technical excellence and creativity to enhance this inspiring environment. Daylight animates the architecture, interacting with the building’s materiality expressed by the concrete arches and timber slats, and creates a visual hierarchy to draw attention towards the altar – illuminated by a shaft of light.
Architectural lighting illuminates the interior at night, creating a rhythm of light and shadow in the slatted timber ceiling that conceals the secondary structures above, showing the simplicity of the architectural form. Daylight apertures and electric lighting work together to reveal the surface qualities of timber and concrete, the simple palette of natural locally sourced materials contrasting with the colours of the equatorial sun and sky.
Central to the functional and design concept, natural light is used to focus attention on the symbolic sanctuary area whilst providing comfortable levels of light throughout the congregational seating and enhancing appreciation of the form and volume of the space.
Natural light sources are embedded in the building fabric, the central roof skylight leading towards the altar, supported by light from the side windows and doors. Most services are held during daytime, yet natural light levels vary considerably in the high altitude, from intense zenithally sunlight to overcast rain filled skies, on an almost daily basis.
The roof skylight design enables a consistent ambience despite these external environmental variations, creating a timeless space within for the congregation. A diffusing glass interlayer scatters daylight, protecting the interior and avoiding piercing sunlight distracting from the service.
The roof skylight also widens towards the altar to modulate daylight so the progression towards the altar is the most prominent element in the visual composition of the interior space.
Lighting simulations and climate based daylighting techniques were key to understanding the performance of the skylight and other daylighting components to create a striking, yet welcoming interior space.
The main light sources used for the project’s lighting design are our simple and elegand track projector Sunluce, outdoor projector Envios IP66 and the pure and minimal suspension mounting fixture Lorosae.