Roofing contractors glossary

Short, plain-English definitions of the terms you'll meet when choosing a roofing contractor provider in Connecticut.

What are algae-resistant shingles?: Roof shingles embedded with copper or zinc granules designed to inhibit the growth of black algae that thrives in humid climates.
What are architectural shingles?: Architectural shingles are laminated asphalt shingles with multiple layers that create depth and shadow lines, offering greater durability and a more textured appearance than traditional 3-tab shingles.
What is a Class 4 impact rating?: A Class 4 impact rating is the highest hail-resistance classification under UL 2218, awarded to asphalt shingles that withstand 2-inch diameter ball bearings dropped from 20 feet without tearing, cracking, or creating holes.
What is a ridge vent?: A ridge vent is a continuous opening installed along the roof peak that allows hot and moist air to escape from the attic, working in combination with soffit vents that draw in cooler replacement air.
What is a roofing square?: A roofing square is a unit of measurement equal to 100 square feet of roof area, used by contractors to calculate labor and material costs.
What is a standing seam metal roof?: A standing seam metal roof consists of vertical metal panels with raised interlocking seams running perpendicular to the slope, with fasteners hidden beneath the seams rather than exposed on the panel surface.
What is a wind uplift rating?: A wind uplift rating is the maximum wind pressure (in pounds per square foot) that a roofing system can resist before the materials begin to lift or separate from the structure, determined through standardized testing.
What is an ice dam?: An ice dam is a ridge of frozen water that builds up along a roof's eave edge during winter, preventing meltwater from draining and forcing it backward under shingles.
What is chimney flashing and cricket?: Chimney flashing is the metal seal around a chimney where it meets the roof, while a cricket is a small peaked structure behind the chimney that diverts rainwater around it.
What is drip edge?: Drip edge is a metal strip installed at the edges of a roof to channel water away from the fascia and protect the roof deck and framing from moisture damage.
What is elastomeric roof coating?: A flexible, liquid-applied membrane coating sprayed or rolled onto flat or metal roofs to seal seams, reflect sunlight, and extend roof life.
What is EPDM roofing membrane?: EPDM (ethylene propylene diene monomer) is a synthetic rubber membrane installed in a single layer on flat and low-slope roofs, typically joined at seams using adhesive or mechanical fasteners.
What is GAF Master Elite certification?: GAF Master Elite is the premium certification tier GAF awards to roofing contractors who meet rigorous training, installation quality, and business standards set by the manufacturer.
What is ice and water shield?: Ice and water shield is a self-adhering bituminous or synthetic waterproof membrane applied to roof decking at eaves, valleys, and penetrations to protect against ice dam damage and water infiltration.
What is modified bitumen roofing?: Modified bitumen is asphalt-based roofing material reinforced with synthetic polymers (rubber or plastic) that is rolled onto low-slope roofs in overlapping sheets to create a flexible, weather-resistant membrane.
What is ponding water?: Ponding water is standing water that remains on a flat roof for more than 48 hours, signaling inadequate roof slope or clogged drainage systems.
What is roof decking?: Roof decking is the layer of plywood or oriented strand board (OSB) attached to roof rafters that forms the structural base for shingles, underlayment, and flashing.
What is roof flashing?: Sheet metal installed at roof joints, penetrations, and edges to direct water away and prevent leaks at vulnerable points where water naturally collects.
What is roof pitch?: Roof pitch is the angle or slope of a roof, expressed as a ratio of rise to run (such as 6/12), which determines water drainage and material compatibility.
What is roofing underlayment?: Underlayment is a weather-resistant membrane or sheet material installed between the roof deck and shingles to block water penetration and protect against leaks.
What is soffit and fascia?: Soffit is the underside material of a roof overhang, while fascia is the trim board attached to the roof edge where gutters mount. Together they protect the overhang and manage moisture and drainage.
What is the difference between manufacturer warranty and workmanship warranty?: A manufacturer warranty covers defects in roofing materials themselves, while a workmanship warranty covers installation errors or labor defects by the contractor.
What is TPO roofing membrane?: TPO (thermoplastic polyolefin) is a single-ply plastic roofing membrane with welded seams, installed on flat or low-slope roofs for durability and solar reflectance.
What is valley flashing?: Valley flashing is the metal or membrane material installed in the valley where two roof slopes meet to direct water runoff and prevent water infiltration.