The term “designer radiator” emerged in the late 1990s as European manufacturers, particularly in Italy and Germany, began producing heating units intentionally styled as architectural or engineered products rather than purely utilitarian panels. They became popular in the UK during the mid-2000s alongside open-plan homes, smaller wall spaces, and improved heat-output testing standards, which made non-traditional shapes viable for primary heating. Demand grew because buyers wanted products that met calculated BTU requirements while fitting modern layouts where standard panel formats were impractical.