Contributions to the sizing of openings for natural lighting in popular homes


The objective of this paper is to contribute to the improvement of the criteria for the evaluation of natural lighting in dwellings, presented in the Brazilian Standard ABNT NBR 15575-5:2013. The minimum values of illuminance established in this standard, both for natural lighting and artificial lighting, do not achieve the minimum values established in the Brazilian Standard ABNT NBR ISO/CIE 8995-1:2013 which deals with the conditions for the visual comfort of the occupants. Thus, environments designed to meet only the minimum criteria for natural lighting may have, as a consequence, not only the visual discomfort, but also additional expenses for the electric energy consumption with the artificial lighting. An estimation was made for the improvement of the use of natural light considering the effective areas of illumination provided by windows found in the Brazilian market for use in dwellings and was compared to the “Daylight Factor” (FLD) values obtained from a set of computational simulations. The simulations were made to determine an illuminance at a central point of the enclosure under three sky conditions for the solstices and equinoxes, from 8:00 a.m. to 5:00 p.m., at 30-minute intervals. In addition, the “Reference Daylight Factor” (FLDr), defined as the relationship between the values of the illuminance established in the Brazilian Standard ABNT NBR ISO/CIE 8995-1:2013 and the external illuminance, was determined. The results show that it is possible to clearly distinguish between window types that can meet the requirements of visual comfort according to the relationship between the size of the environment and the window lighting area. Based on these aspects, the requirements and the criteria of ABNT NBR 15575-5:2013 can be improved to ensure minimal visual comfort and to reduce energy consumption for artificial lighting.


ALVES NETTO, Ary Rodrigues; BARRETO, Douglas; BRITO, Adriana Camargo de; AKUTSU, Maria. Contribuições para o dimensionamento de aberturas para iluminação natural em habitações de interesse social. Revista IPT Tecnologia e Inovação, v.2, n.9, p.14-23, dez., 2018.

Access to the article on the newspaper website:

SUBSCRIBE to our newsletter

Receive our news in your email.

INSCREVA-se em nossa newsletter

Receba nossas novidades em seu e-mail.