New fire barriers combining the use of two different intumescent paints and a metal laminate structure have been evaluated for the protection of steel. Different bilayer designs have been considered and are composed of an overlay of two intumescent coatings with or without aluminum foils. All laminated bilayers were exposed to fire in a high-temperature environment (116 kW/m2). The design with two aluminum foils and the overlay of both intumescent coatings reveals efficient fire protection with stabilization at low temperatures after 30 min of fire exposure. This design exhibits much higher performance than that of the conventional intumescent coating. Characterizations (cross-sectional observations, expansion measurements, and pull-off tests) were performed for all samples to clarify the mechanism of action. This paper reveals a new way of thinking and highlights that working on the design instead of changing the formulation of the intumescent paint allows us to reach an efficient fire-resistant barrier.