Roofing 101 – Key Terms & Definitions

• New Con Roofing: The installation of a new roofing system on a newly constructed building.
• Re-Roofing: The removal of an existing roofing system down to the structural decking and the installation of a new roofing system.
• Recover Roof System: The installation of a new roofing system over and existing roofing system.
• Retrofit Roof System: The application of a new roof system, typically a single ply roof system over an existing metal roof system. Occasionally a retrofit can be where a sloped roof system is fabricated and installed over a flat roof.
• Preventative Maintenance: Usually is in conjunction or post roof inspection. it is where an existing roof system and components are brought back to good working condition. This could include a roof coating system.
• Roof Restorations: Is similar to preventative maintenance work, but on a much larger scale. Typically, the replacement of base, curb and penetration flashing as well as sheet metal are performed while the existing roof system is left in place. This can also be classified under a roof coating system.
• Scope Work: This is over and above a common roof repair. This can include; Fit out work; metal flashings; roof flashing; penetration replacements; roof hatch replacements /installations; gutters & downspout replacements; roof drainage replacements/repairs.
• Low Slope Roofing: Typically are products installed on roofs of 2/12 or less, examples are architectural shingles, architectural metal panels, and tile.
• Steep Slope Roofing: Typically are products installed on roofs of 2/12 or greater, examples are modified bitumen, BUR, TPO, PVC, or EPDM.
• BUR/BURG: Built up roof/ Built up gravel roof system typically asphalt based roof systems.
• Modified Bitumen: Asphalt based rolled roofing membranes ( torch, cold adhesive, peel & stick or asphalt applied).
• TPO: Thermopolyolefin (TPO for short) is a single ply roof system that is typically installed on low slope roof systems (mechanically fastened or fully adhered “Glued”. The product is normally white in color and the seams are welded together. This is a younger product when compared to PVC.
• PVC: Polyvinyl Chloride (PVC for short) is a single ply roof system that is a typically installed on low slope roof systems( mechanically fastened or fully adhered “Glued”. The product is normally white in color and the seams are welded together. This is an older product when compared to TPO.
• EPDM: EthylPropolenDieneMonomer (EPDM for short) is a single ply roof system that is typically installed on low slope roof systems (mechanically fastened or fully adhered “Glued”. The product is normally black in color and the seams are glued together.
• Structural Metal Roofing: Metal roofing systems typically installed over open framing.
• Architectural Metal Roofing: Metal roofing systems typically installed over a structural deck.
• Dimensional Shingles: Asphalt based shingles with an added architectural design.
• 3-Tab Shingles: Asphalt base shingles with 3 distinctive tabs and no additional designs.