Improving the daylighting performance of residential light wells by reflecting and redirecting approaches

•Light wells are improved by the use of reflective materials and redirecting device.•Effects of diffuse and specular reflective materials are investigated.•Solar redirecting devices are efficient in different latitudes and climates.•“Blind Days”, a climate-based daylight metric to assess dark spaces, is proposed.•A radiosity method with extended view factors suited to this context is developed.