McDonald's 1960s restaurant concept featuring a mansard roof was known as the Mansard Roof design.
The design replaced the earlier walk-up buildings with a more substantial restaurant form using a steep, decorative mansard roof, broad glass fronts and prominent Golden Arches signage. It was developed during the 1960s as McDonald's shifted toward recognizable roadside restaurants suitable for rapid national expansion.
Architectural consistency became a branding tool: customers could identify a McDonald's from a distance before reading the sign. The mansard roof also helped distinguish the chain from competing hamburger stands and tied the building to the emerging Golden Arches identity.
Later decades introduced many variations, including modern flat-roof and digitally branded restaurants. “Mansard Roof” refers to a historical architectural era, not every building that ever displayed arches.