The brick production industry faces increasing environmental pressure due to high energy demands during firing, necessitating the optimization of firing conditions. This study investigates an eco-friendly stepped firing process as a sustainable alternative to conventional direct heat treatment using clayey raw materials from the Ouled Mansour area, north-east Morocco. To evaluate this approach, raw materials were characterized using X-ray diffraction, X-ray fluorescence, infrared spectroscopy, simultaneous thermal analysis, Atterberg limits and particle-size distribution analysis. Brick specimens were then prepared and fired under both conventional and stepped heating processes. Their thermophysical properties (thermal conductivity, thermal diffusivity, porosity, water absorption and density) and compressive strength were assessed. Non-destructive tests (ultrasonic pulse velocity and Schmidt hammer tests) together with mineralogical and microstructural analyses were also performed. The stepped firing process reduces porosity and defects, thereby increasing the ultrasonic pulse velocity from 3197 to 3508 m s–1 and improving compressive strength by up to 21%. Thermal conductivity and density slightly increase, from 0.57 to 0.58 W mK–1 and from 1.60 to 1.62 g cm–3 at 770°C, respectively. The proposed eco-friendly firing process enhances the physico-mechanical performance of bricks while supporting their energy-efficient production, with potential reductions in energy consumption during both manufacturing and the building service life.
