The 'LIGHTVAN' research aims to optimize the lighting design for healthy schools and modern senior housing and care homes with regards to the use of light as a cheap and important source of energy. A multi-functional mobile light laboratory was built into a delivery van, the LIGHTVAN. This LIGHTVAN has two clear aims: With this mobile light laboratory we can travel to the living environment of specific groups of people, such as children and seniors, so that they may be subject to specific age-dependent light studies. In this moving laboratory measurement equipment is present for this purpose and a table and chairs for the various subjects. Testing of luminance and color contrasts are possible, as well as the testing of "light and shadow" patterns. Even small eye tests can be performed. In addition, the rear side of the delivery van is adapted so that with opened doors all kinds of innovative facades can be tested. The LIGHTVAN travel to different locations to be accommodated and be positioned towards various sun directions. Several passe-partouts are available for building physics measurements of different facades sizes in order to allow test-subjects to indicate their preferences for specific facades in terms of comfort.