OSB

More roofing & materials terms

• Nail pattern

  The spacing and placement of nails that fasten shingles or sheathing, set by the shingle manufacturer and the local code. It is checked during roof inspections, and an improper pattern is a common reason a carrier denies or prorates a shingle repair.

• Nail pop

  A fastener that has backed out and is lifting the surface above it - a shingle on a roof, or the painted surface of drywall inside - usually from movement, heat cycling, or a fastener that missed the framing. A few are a repair; pops across a whole slope usually point to an installation or ventilation problem rather than to wind or hail, and that pattern is often not covered as storm damage.

• Parapet wall

  The low wall that extends above the roofline at the edge of a flat or low-slope roof, often on commercial buildings and sometimes on homes. It gets its own flashing, coping, and sealant line items, and those details are commonly missed when a scope is written from photos.

• Peel-and-stick membrane

  A self-adhering roofing membrane, often used as underlayment on steep-slope roofs or as a cap sheet on low-slope roofs, that seals around nails and resists ice dams. It is priced by the square, and where it is required depends on the local code.

• Pipe boot

  The rubber or metal seal around vent pipes that stick through the roof.

• Pipe collar

  The flashing piece that seals a roof where a plumbing vent pipe passes through it, also called a pipe boot. Collars crack with sun exposure, and a failed collar is a leading source of small roof leaks, so it appears as its own line item on a repair scope.

Common questions