Glossary: 100 Important Roofing Terms

Glossary: 100 Important Roofing Terms

Use this glossary as a quick reference as you navigate your roofing job.


  • Asphalt Shingles: Common roofing material made from asphalt for waterproofing.
  • Apron Flashing: A term for metal flashing used at chimney fronts.


  • Barge Board: A board fastened to the projecting gables of a roof.
  • Bitumen: A black, sticky substance used in certain roofing materials.


  • Cricket: A peaked water diverter installed behind chimneys or along roof ridges.
  • Counterflashing: Metal flashing that's installed to prevent moisture entry.


  • Decking: The substrate over which roofing is applied, usually plywood or OSB.
  • Dormer: A protruding mini-roofed structure with a window.


  • Eaves: The lower border of the roof that overhangs the walls.
  • EPDM (Ethylene Propylene Diene Monomer): A durable synthetic rubber roofing membrane.


  • Flashing: Materials used to waterproof a roof around any projections.
  • Fascia: A board that runs along the roof's edge, connecting the roof and the outer walls.


  • Gable: The triangular portion of a wall between the edges of intersecting roof pitches.
  • Granules: Mineral particles coated on the surface of shingles.


  • Hip Roof: A roof with sloping ends and sides.
  • HVAC Penetrations: Vents or exhausts for heating, ventilation, and air conditioning systems.


  • Ice Dam: A ridge of ice that forms at the edge of a roof and prevents melting snow from draining.
  • Insulation: Material used to keep heat in or out of a home.


  • Joist: Horizontal structures that support the decking.
  • J-Channel: A type of trim used around windows and doors on the roof.


  • Kick-Out Flashing: Flashing that diverts water away from the cladding.


  • Laminated Shingles: Shingles containing more than one layer of material for durability.
  • Louvers: Slatted devices installed in a gable or soffit for ventilation.


  • Membrane: A type of roofing system for flat roofs, made from modified bitumen.
  • Mansard Roof: A four-sided gambrel-style hip roof.


  • Nesting: Installing a new layer of shingles over an old layer.
  • NRCA (National Roofing Contractors Association): An association that represents all aspects of the roofing industry.


  • Overhang: The portion of the roof structure that extends beyond the exterior walls.
  • OSB (Oriented Strand Board): A type of decking material made from compressed wood strands.


  • Pitch: The angle or slope of a roof.
  • Ply: A layer of roofing (in felt, ply sheet, etc.).


  • Quarter Sawn: A type of wood cut that's less likely to warp.


  • Rafter: The supporting framing to which the roof deck is attached.
  • Ridge: The top edge of two intersecting sloping roof surfaces.


  • Soffit: The exposed surface beneath the overhanging section of a roof eave.
  • Shingle: A piece of roofing material that is laid in overlapping rows.


  • Tar: A black, viscous material used in roofing.
  • Truss: A framework, typically consisting of rafters, posts, and struts, supporting a roof.


  • Underlayment: A layer of material placed beneath shingles to provide additional protection.


  • Valley: The internal angle formed by the intersection of two sloping roof planes.
  • Vapor Barrier: Material used to prevent moisture from penetrating the roof.


  • Warranty: A promise by the manufacturer or roofer regarding the quality and performance of roofing materials or work.
  • Weep Holes: Small openings that allow for water drainage.


  • Xactimate: A software used for estimating construction and repair costs, commonly in roofing.


  • Yield Point: The point at which a material begins to deform permanently.