aleros

Aleros are architectural features consisting of the projecting edge of a roof that overhangs the wall of a building. The plural form aleros refers to multiple such edges. In English, the equivalent terms are eaves or roof overhangs. The concept is common in many languages and regions where buildings are designed to shed rain and regulate heat.

The primary function of aleros is protective and climatic. By extending beyond the wall, they deflect rainwater away from the façade, helping to prevent moisture-related damage and mold. They also provide shade, reducing direct solar gain on walls and windows, which can lower indoor temperatures in hot climates. In traditional architecture, especially in Spain and many Latin American countries, deep aleros are a characteristic feature of vernacular design.

Construction and variation vary by region and period. Aleros are typically formed by the edge of the roof, sometimes supported by rafter tails, brackets, or a fascia board. They may be simple or elaborately decorated, with wooden dentils, corbels, or ceramic tiles in decorative eaves. In some climates, they are wide and flat to create outdoor shaded corridors, while in others they are narrow and functional.

Maintenance considerations include inspecting for water intrusion at the wall line, rot in timber structures, insect damage, and paint or sealant wear. Proper drainage and periodic repairs help preserve the effectiveness and appearance of aleros for both functional and aesthetic purposes.

See also: eaves, roof overhang, fascia, cornice.