MIT Sustainable Design Lab
Glare Analysis of Daylit Spaces

Alstan Jakubiec and Christoph Reinhart (supported by the NSF)
Adaptive Comfort Paper | Tutorial on Glare Analysis with Evalglare

Glare, physical discomfort caused by contrast or luminous intensity, is an underutilized parameter in contemporary architectural design. This project consists of a series of related activities that are concerned with experimental and computer-based design analysis techniques to asses the appearance of glare in daylit spaces.

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1 - In a 2011 survey 80% of participants voted glare to be either an important or extremely important design consideration. (Mogri)

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2 - High Dynamic Range (HDR) Photography is an innovative way to characterize the visual environment in daylit spaces.

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3 - Two tutorials on HDR Photography can be found under Teaching Resources>>Glare. (Doyle)

Adaptive Visual Comfort

In this study we compared simulation results for five glare metrics under 144 clear sky conditions in three spaces in order to investigate the ability of these metrics to predict the occurrence of discomfort glare and to hence support the design of comfortable spaces. The metrics analyzed are Daylight Glare Index, CIE Glare Index, Visual Comfort Probability, Unified Glare Rating, and Daylight Glare Probability. It is found that Daylight Glare Probability yields the most plausible results. In an attempt to deal with multiple positions and view directions simultaneously, the concept of an 'adaptive zone' is introduced within which building occupants may freely adjust their position and view in order to minimize the effect of glare. The spatial and directional extents of the adaptive zone depend on furniture layout and the freedom of occupants' tasks. It is found that applying the adaptive zone concept to a sidelit office with manually operated venetian blinds reduces the predicted hours of intolerable discomfort glare from 735 to 18 occupied hours per year and increases the annual mean daylight availability from 40 to 72 percent. Adaptive Comfort Paper

The animated image above shows a cylindrical 360o view of a work space in a studio sapce. The color coded lines at the bottom show the predictions of different glare indices (DGP, DGI, UGI, CGI and VCP) whether discomfort glare will be experienced in a particular direction at at different times of the day (Green=Imperceptible Glare; Yellow=Perceptible Glare; Orange=Disturbing Glare; Red=Intolerable Glare).