Are light wells in residential building able to light environments?

Abstract

The study starts from a recurring situation in housing settlements. It aims to bring contributions to the standard revision and to the municipal regulations with an impact on the daylight admission. The study developed 280 analysis of daylighting performance for a living room with a window facing a light well, located on the 1^st and 4^th floors of a multifamily housing unit, in Belo Horizonte - MG. The analysis used the prescriptive methodology of the NBR15.575/2013 standard and by computer simulation. The analysis of the external illuminance levels showed that on the 1^st floor there is little availability of natural light in the well, causing reduced daylighting performance in the environment. The level of 48 lux, minimum level of NBR 15.575/2013, for the first floor was not reached. The widening of the diameter of the well from 3 to 6 meters (D3 and D6) does not significantly improve the daylighting conditions in the internal environment, which happens only in the vertical elevation of the environment to the upper floors. On the 4^th floor the level of 60 lux was reached only with D6 diameter of the well. The adoption of internal and external walls with reflectance of 80% can increase this performance by approximately 80%, in relation to reflectance between 50-60%, especially in conditions in which there is no contribution of the sky component, and there is a high contribution of the internal and external reflected component, as is the case of environments facing the light well.

Keywords: daylighting, light well, illuminance.