The transwall system, proposed and developed by Fuchs and McClelland, fulfills the function of a passive solar heating device as well as an architectural element the window. The significance of the transwall system, in the author's opinion, lies in its expression of technologies in an architectural way. Several directions for further development are suggested to modify the transwall system into a multifunction architectural element so as to maximize utility. These architectural uses are: (1) an adjustable thermal mass; (2) a passive cooling device; (3) an interior design element; (4) a component of a convertible greenhouse and living space; and (5) a shading device. / M. Arch.