Building underground with a touch of light
In many places all over Europe, skyscraper constructions have been met with financial woes, and social and political challenges. This situation has provided the impetus to urban planners to look below ground for a solution to the traffic congestion and development challenges. However, any underground space developed would be covered to maximise land use, thus preventing natural light shining through. With EU funding of the project SKYCOAT (Sky like coating materials for hypogeal and skyscrapers architectures), project members sought to recreate in the underground the experience of natural light from the Sun and diffused sky lights. Reproducing daylight in hypogeal spaces dispels any negative psychological emotions and opens new territory to real estate investors, architectural and lighting designers, and the public. SKYCOAT technology is based on advanced nano-structured dichroic materials that faithfully reproduce the same Rayleigh scattering that occurs in the atmosphere, creating the celestial blue. Light-emitting diode projectors were developed in tailored sizes, shapes and peculiar luminance, and spectral and angular distribution, emitting a rectangular light beam, a low-divergence beam and a linear beam. Project members also designed a lamp that recreates the light hitting a window that is covered by a curtain and a recessed lamp that is well suited for use in corridors. In addition, SKYCOAT technology was used to tailor the perceived silhouette of skyscrapers or other buildings, and to recreate the idea of a window on a room ceiling. Two socio-clinical studies were conducted on 200 people to assess the effects of SKYCOAT lighting technologies on their perception, comfort and well-being. The study verified that even constrained spaces are perceived as comfortable and much wider when lightened by SKYCOAT systems. In addition, they reduce stress and enhance productivity compared to artificial lighting. SKYCOAT's groundbreaking technology is creating a kind of skylight that perfectly mimics daylight and tricks people into thinking that they are looking up at the actual Sun.
Keywords
Underground, natural light, hypogeal, skyscraper, SKYCOAT
