Today’s predictions of visual comfort are based on high-quality physically-based visualization renderings. Unfortunately, designers and practitioners rarely realize the full benefit of physically-based lighting simulation due to the amount of time required for these simulations. Visual comfort analysis is generally performed late in the design process as a form of validation, if at all. We propose a design workflow wherein certain quantitative visual comfort metrics can be displayed immediately to the designer as the scene changes, often before the physically-based visualization reaches a finished quality. In our prototype software, live-updating predictions of daylight glare probability, task luminance, and contrast are presented alongside a progressively rendered image of the scene so that the user may decide when to accept the values and move on with the design process. In most cases, sufficiently accurate results are available within seconds after rendering only a few frames.