This document discusses light and heavy building facades and where the limit between them lies. It examines several case studies of different facade systems, including a light steel frame system, aluminium curtain walling, a solid wood slab system, and single-leaf masonry walls. It also explores design criteria and factors that determine whether a facade is considered light or heavy, such as weight efficiency, payload to mass ratio, and performance regarding hygrothermal behaviour, fire resistance, acoustics, and life-cycle considerations. The document suggests there is still work to be done in understanding where exactly the limit between light and heavy facades should be drawn.