Roofing Terminology

Ponding Water: Standing water not draining off roof system. Can damage roof membrane and enter building envelope.

Flashing: A protective covering placed around roof penetrations/roof perimeter. Stops water penetrating roof.

Blueberries: These are the result of dried out surface asphalt.

Windswept: High winds can remove metal and stones from the roof pitch pocket is traditionally a metal boot or pipe sleeves that are used to create a water tight seal in a roof penetration that allows electrical cable and items to enter the building to provide power etc.

Decking: The substrate that the roof is sitting on. Can be metal, wood, or concrete.

Exposed felts: Areas lacking in surface asphalt, mineral, granule, or aggregate due to wind and water erosion.

Expansion/Control Joint: is an assembly designed to safely absorb the heat-induced expansion and contraction of construction materials.

Penetrations: Anything that you can see on top of the roof including perimeters, HVAC units, pitch pockets, vent stacks.

Core cut/Core sample: Cutting through the membrane of the roof down to the deck for investigative purposes.

Splits: Splits in a membrane can be caused by the expansion and contraction of the building. Old and weakening membranes are no longer flexible and eventually fail.

Ridges: You will see these on the surface of Built up roofs B.U.R as linear buckling upward through the layers of asphalt.

Alligatoring: A result of the drying out and shrinking of the asphalt surface.

Blisters: Appear to be giant bubbles at the surface of the roof.

Curbs: Raised frame used to mount mechanical units (air conditioning or exhaust fans), skylights, etc. on a roof.

Parapet Wall: Is a barrier which is an extension of the wall at the edge of a roof, terrace, balcony, or other structure.