Browse our comprehensive collection of roofing terms and definitions
The structural panel layer—often OSB or plywood—that supports underlayment and roof covering. Delamination or rot from l...
Written findings with photos describing materials, approximate age, visible defects, and maintenance recommendations. Ma...
Installing a new layer over an existing roof where codes, weight, and deck condition allow. Not suitable for all systems...
A secondary water-shedding layer between the roof deck and the primary covering. Synthetic underlayments are common unde...
Drainage paths for parapet and low-slope roofs: scuppers through walls or internal drains with sumps. Clogged drains cau...
Often originate at curb flashings, lens seals, or condensation management on humid monsoon nights—not always the glazing...
Intake openings in the underside of eaves that feed cool air into attics. Insulation baffles keep channels clear from bl...
Mounts and flashings that maintain watertight seals around PV rack posts or rail bases; should be evaluated anytime pane...
Closed-cell foam sprayed over low-slope decks, then protected with coatings or granules. Common on commercial and some r...
Interlocking concealed-fastener metal panels that shed water and resist wind. Reflective finishes and proper attic venti...
Individual box or turtle-style exhaust vents cut into the roof deck. Placement and net free area must be calculated with...
Individual pieces laced with each shingle course where a roof meets a vertical wall. Corrosion, separation, or missing p...
Heat-weldable thermoplastic membrane used on commercial low-slope roofs. Seams and penetrations are the primary inspecti...
Removing existing coverings (and sometimes underlayment) before installing new materials. Allows full deck inspection an...
Rapid heating and cooling cycles that stress coatings, single-ply seams, and some tile mortars—common when hot days cool...
Replacing fractured tiles, re-securing slipped pans, and renewing foam or mechanical clips per manufacturer guidance to...
W-shaped or closed-cut valley flashing that channels high-volume runoff. Debris accumulation in valleys is a common leak...
Progressive failure where negative pressure lifts shingle seals or displaces tile; often begins at corners, rakes, and l...