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Mike Lofaro1 min read

Parts of a Roof

Getting leaks? Cupped shingles? A remarkable crop of plants growing up there? Time for a new roof. It might help if you have the 101 on what makes a roof…a roof. Here are some basic components of the typical roof. Knowing what you have and getting what you need will help make your investment in your home last for decades.

roofing diagram resized 600

Dormer:The structure that surrounds 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: The wood (plywood) that covers the rafters. The base to which the roofing materials are attached.

Underlayment: Heavy felt paper or synthetic skin is placed on top of the decking before the roofing material is installed to offer an additional layer of protection from moisture.

Drip Edge: Placed at the edges of the roof and helps allow water to run-off and drip clear of underlying construction.

Fascia trim: Covers the rafter end of the eaves. Often where gutters are attached to the house.

Soffit: Is a finished underside of the eaves. Covers the area between the end of the eaves and the house.

Valley: The angle formed when by the intersection of two sloping roof planes. The intersection of a cross hip or cross gable roof.

Hip: The high angle formed by the intersection of two sloping roof planes.

Gable: A 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.

Ridge Vent: Allows ventilation of the structure through the highest point at the ridge of the home.