Dormer - the structure (walls and roof) around a window that projects from a sloped roof.
Roof Truss the skeleton of the roof. A framework of beams that support the roof.
Rafters The beams that run from the top of the roof to the bottom. Part of the roof truss.
Decking or Sheathing Panels that cover the rafters and to which the roofing material (shingles, metal panels, etc..) are attached.
Underlayment often called tar paper this heavy felt paper (synthetic materials are available as well) is placed on top of the decking before the roofing material is installed to offer an additional layer of protection from moisture.
Drip Edge edging that is placed at the end of the roof (end of the eaves) used to allow water to run-off and drip clear of underlying construction.
Fascia trim used to cover the rafter end of the eaves. Often where gutters are attached to the house.
Soffit a finished underside of the eaves. Covers the area between the end of the eaves and the house.
Valley - internal angle formed when by the intersection of two sloping roof planes. The intersection of a cross hip or cross gable roof.
Hip - external angle formed by the intersection of two sloping roof planes.
Gable triangle shaped part of the end of a building underneath the roof and above the main portion of the house.
Ridge the highest point of the roof that runs the length of the roof.
Flashing - Pieces of metal used to prevent the seepage of water around any intersection or projection in a roof, such as vent pipes, chimneys, valleys, and the joints at vertical walls.
Starter Strip - Asphalt roofing applied at the eaves that provides protection by filling in the spaces under the cutouts and joints of the first course of shingles.