The most well-known example is Finnish modernist architect Alvar Aalto who would create aesthetic effects in the facades of his buildings through the combination of different types and sizes of louvers . Some are fixed and some are moveable . The most well-known example is Finnish modernist architect Alvar Aalto who would create aesthetic effects in the facades of his buildings through the combination of different types and sizes of louvers , some fixed some moveable , and made mostly from wood ( e.g. the various buildings of the Helsinki University of Technology ) .