A rafter is a structural beam that runs from the ridge of a roof down to the eaves, providing the sloped support structure for roofing materials. Rafters bear the weight of the roof covering, insulation, and any snow loads, transferring this weight to the building's walls. Traditional stick-built roofs use individual rafters, while modern construction often uses pre-fabricated trusses. Building codes specify rafter sizes, spacing, and construction requirements based on roof span, pitch, and local conditions. Building inspectors check rafter construction during framing inspections. Proper rafter installation is essential for roof integrity and building safety.