The words you'll hear from a roofer
Plain-English definitions for the terms used on quotes, insurance scopes, and inspection reports — so you can make informed decisions about your roof.
3
3-Tab Shingle
A flat, single-layer asphalt shingle with three uniform tabs. Lowest cost and the thinnest profile; largely replaced by architectural shingles.
A
ACV (Actual Cash Value)
The depreciated value of your roof at the time of loss. Older policies or older roofs often pay ACV only.
Algae Streaks
Dark horizontal stains caused by Gloeocapsa magma algae — common in humid climates.
Architectural Shingle
A multi-layer "dimensional" asphalt shingle that simulates the depth of wood shakes. Standard on most modern homes.
Asphalt Shingle
The most common residential roofing material, made of a fiberglass mat coated in asphalt and surfaced with mineral granules.
Attic Ventilation
The balanced airflow (intake + exhaust) that keeps an attic dry and cool — critical for shingle longevity.
B
Blistering
Raised bubbles on shingles, usually caused by moisture trapped in the mat or poor attic ventilation.
Boot / Penetration
Any object passing through the roof (pipes, vents, skylights) that needs its own flashing.
Box Vent
A passive static vent installed near the ridge to release attic heat.
Built-Up Roof (BUR)
A traditional multi-ply flat roof made of alternating layers of bitumen and fabric, finished with gravel.
C
Counter Flashing
A second flashing piece mounted into a chimney or wall to cover the top edge of step flashing.
Curling
Shingle corners that turn upward — a sign of age, poor ventilation, or heat stress.
D
Deductible
The portion of a claim you pay before the insurer pays anything. For roofs, this is often 1–2% of the dwelling limit.
Dormer
A vertical window projection that sticks up from a sloped roof.
Downspout
The vertical pipe that carries water from the gutter to the ground.
Drip Edge
Metal flashing installed at the eaves and rakes to shed water away from the fascia and deck.
E
Eave
The lower horizontal edge of a roof where the gutter is attached.
EPDM
Ethylene Propylene Diene Monomer. A black synthetic-rubber single-ply flat-roof membrane known for longevity.
Exposure
The portion of each shingle left visible after the next course overlaps it — typically 5-5/8 inches.
F
Fascia
The vertical board that runs along the eave where gutters are mounted.
Flashing
Thin metal pieces installed around chimneys, walls, skylights, and valleys to direct water away from joints.
G
Gable
The triangular wall section between two sloping roof planes.
Granule Loss
Loss of the mineral granules that protect asphalt shingles — common in older roofs or after hail.
Gutter
The channel along the eave that collects rainwater from the roof and directs it to downspouts.
Gutter Guard
A screen or cover installed over a gutter to keep out leaves and debris.
H
Hip
An external sloped edge where two roof planes meet (not the ridge).
I
Ice & Water Shield
A self-adhered membrane installed in valleys, along eaves, and around penetrations to block wind-driven rain and ice dams.
Ice Dam
A ridge of ice formed at the eave that blocks meltwater and forces it back under the shingles.
Impact-Resistant Shingle
A Class 4 UL 2218–rated shingle designed to resist hail. May earn an insurance discount in Texas and Louisiana.
L
Lifting
Shingles that have lost their seal, often after high winds or improper installation.
Linear Footage (LF)
The total length of an edge feature (ridge, hip, valley, eave, or rake) in feet.
Low Slope
A roof with a pitch less than 2/12 — requires membrane or built-up systems, not shingles.
M
Manufacturer Warranty
Coverage on shingles themselves — covers defects in materials, not workmanship.
Metal Roofing
A long-life roof made of steel, aluminum, copper, or zinc — available as standing-seam panels or stone-coated steel.
Modified Bitumen
A multi-ply asphalt-based flat-roof system (torch-down or peel-and-stick) used on low-slope roofs.
N
Nail Zone
The manufacturer-specified band on each shingle where nails must be placed for the warranty to apply.
O
Overlay / Recover
Installing new shingles directly over an existing layer. Most codes allow at most two layers total.
P
Pipe Boot
A flashing collar with a rubber gasket that seals around plumbing vent pipes.
Pitch
The steepness of the roof, typically expressed as rise-over-run (e.g., 6/12 means 6 inches of rise per 12 inches of run).
Plane / Facet
A single flat surface of the roof bounded by eaves, rakes, hips, valleys, or the ridge.
Ponding Water
Water that remains on a flat roof more than 48 hours after rain — warranty exclusion on many membranes.
Power Vent
A fan-driven attic exhaust vent, often solar or thermostat-controlled.
PVC Membrane
A heat-welded single-ply flat-roof membrane that resists chemicals and grease — popular on restaurants and warehouses.
R
Rafter
A sloped framing member that supports the roof deck. Modern homes often use trusses instead.
Rake
The sloped, angled edge of a gable roof.
RCV (Replacement Cost Value)
The full cost to replace your roof with like-kind materials — paid in two parts (ACV up front, depreciation after completion).
Ridge
The highest horizontal edge where two roof planes meet at the peak.
Ridge Cap
Thicker, hip- and ridge-specific shingles that bend over the peak to finish the roof.
Ridge Vent
A continuous vent running along the ridge that exhausts hot attic air.
Roof Deck
The structural wood (plywood or OSB) that roofing materials are fastened to.
S
Scupper
An opening in a parapet wall that lets water drain from a flat roof to the exterior.
Seamless Gutter
Gutter formed on-site in one continuous piece (except at corners) to minimize leaks.
Soffit
The underside of the roof overhang, usually vented to allow attic airflow.
Soffit Vent
Intake vents installed in the soffit that let cool air into the attic.
Square
100 square feet of roofing. Materials and labor are priced per square.
Standing Seam
A metal roof with raised, interlocking vertical seams between panels. Fasteners are hidden.
Starter Strip
A pre-adhered strip installed at the eaves and rakes so the first course of shingles has a factory seal.
Step Flashing
L-shaped flashing pieces woven between shingles where a roof meets a vertical wall.
Supplement
An additional payment request filed with the insurer for items missed in the original scope.
Synthetic Underlayment
A woven-polymer underlayment that outlasts traditional felt and is safer to walk on.
System Warranty
An upgraded manufacturer warranty (e.g., GAF Silver Pledge, Golden Pledge) that covers the full roof system when installed by a certified contractor.
T
Tear-Off
Complete removal of the old roof down to the deck before installing a new one.
TPO
Thermoplastic Polyolefin. A white, single-ply commercial flat-roof membrane that reflects heat and is heat-welded at the seams.
Truss
A pre-built triangular framing assembly that supports the roof and ceiling.
U
Underlayment
A layer rolled over the roof deck before shingles are installed. Adds a second line of defense against water.
V
Valley
An internal angle where two roof planes meet — a natural channel for runoff.
W
Waste Factor
Extra material (usually 10–15% for steeper or cut-up roofs) ordered to account for cuts, breakage, and pattern matching.
Workmanship Warranty
Coverage on the installer's labor — separate from the manufacturer warranty.