The presented book deals with the use of Wire Arc Additive Manufacturing (WAAM) as a means of stiffening and reinforcing free-form sheet metal as an application in facade. The main focus of the research is developing a methodology for welding ontop of pre-bent sheet metal; including digitizing of arbitrarily-formed sheet metal, developing of process-parameters for welding on thin sheet metal and generating force-responsive welding paths. The research is focused on singly-curved sheet metal profiles, and is concluded by the production of a number of small-scale prototypes which illustrate the potentials for reinforcing sheet metal using WAAM.