What is the purpose of eaves in roof design?

Eaves play a crucial role in roof design primarily by directing water away from the walls and foundation of the structure. When rainwater falls on the roof, the eaves extend out beyond the walls to create an overhang. This overhang helps to funnel water away from the building, minimizing the risk of water damage to the walls and preventing unnecessary moisture accumulation at the base of the structure. This function is particularly important as it contributes to the longevity of the building materials and helps to prevent issues like mold growth and structural deterioration.

While eaves can also enhance the aesthetic value of a building and may support the roof structure to some extent, their primary and most critical function is to manage water drainage. Improving insulation is not a common role of eaves, as insulation typically pertains to materials and techniques used in the roof and walls themselves, rather than the architectural components like eaves. Therefore, directing water away from the walls is the most relevant purpose of eaves in roof design.