It feels great to get outside on a beautiful day to go on a hike, bike ride or even a lazy walk around the neighborhood. Along with exercise, much of the energy a person gains from outdoor activity comes from getting some sun -it’s great for mind, body & soul! However too much sun isn’t a good thing for your skin, so you better wear some SPF? Good indoor daylight is healthy too, both for buildings and their occupants. However, as mindful as people are of getting too much outdoor sun, attention also needs to be applied to how building interiors receive sun.