Roof eaves is the lower edge of the roof slope, projecting beyond the face of the building wall. Its function is to protect the façade and the foundation area from the direct effects of rainfall. The eaves also allow for the proper termination of the roof covering and the installation of a gutter system to channel rainwater.
From a structural point of view, the eaves are often an extension of the rafters, supported by an eaves board, soffit and guttering. It can be open (with the rafters visible) or enclosed (e.g. with a timber, PVC or aluminium soffit). A well-designed eaves improves the aesthetics of a building and its resistance to weathering. In energy-efficient construction, the length of the eaves is sometimes adapted to the angle of the sun's rays in order to limit overheating of the interior in summer.
