GEORGIA & FLORIDA · ROOFING GLOSSARY
Roofing Terms Glossary — Roofing Words Explained in Plain English
Roofing estimates are full of jargon — squares, decking, drip edge, underlayment, wind mitigation. This A-to-Z glossary explains the 30+ roofing terms you’re most likely to run into, in plain English, so you can read your estimate and talk to your contractor with confidence. Have a term we didn’t cover? Just ask us.
Why This Helps
Understand Your Roof Before You Sign
A roof is one of the biggest investments in your home, and it’s hard to make a confident decision when the estimate reads like a foreign language. The terms below are the ones that come up most often on Georgia and Florida roofing projects — from the parts of your roof system to the storm and insurance vocabulary you’ll hear during a claim. Skim it, or search for the word you need.
A – D
Roofing Terms: A to D
Architectural shingle — A dimensional asphalt shingle with a layered, textured look. More durable and better-looking than flat “3-tab” shingles, and the most popular residential choice in Georgia.
Asphalt shingle — The most common residential roofing material: a fiberglass mat coated in asphalt and mineral granules. Affordable, versatile, and widely used across the Southeast.
Cricket — A small ridged structure built behind a chimney or other obstruction to divert water around it rather than letting it pool.
Decking (sheathing) — The wood boards or plywood/OSB panels nailed to the rafters that form the structural surface everything else attaches to. Rotten decking is a common hidden repair found during tear-off.
Drip edge — A metal flashing installed along the roof’s edges to guide water off the roof and away from the fascia and decking. Often required by code.
E – H
Roofing Terms: E to H
Eave — The lower edge of the roof that overhangs the exterior wall. This is where drip edge, gutters, and ventilation intake often live.
Fascia — The vertical board that runs along the roof’s edge, behind the gutters. It caps the rafter ends and gives the roofline a finished look.
Flashing — Metal pieces installed at joints, valleys, chimneys, walls, and other transitions to seal out water where two surfaces meet. Failed flashing is a leading cause of leaks.
Gable — The triangular section of wall at the end of a pitched roof, formed where two roof slopes meet.
Granules — The mineral grit bonded to the surface of asphalt shingles. Granules protect the asphalt from UV and add fire resistance; heavy granule loss is a sign of aging or hail damage.
Hip roof — A roof where all sides slope down to the walls, with no vertical gable ends. Hip roofs perform well in high wind, which matters for Florida wind-mitigation credits.
I – P
Roofing Terms: I to P
Ice & water shield — A self-adhering waterproof membrane applied in vulnerable areas like valleys and around penetrations for extra leak protection.
Impact-resistant (Class 4) shingle — A shingle that passed the highest rating on the UL 2218 impact test, built to resist hail damage. A popular upgrade in North Georgia’s hail belt — see our roof replacement options.
Low-slope / flat roof — A roof with little or no pitch, typically covered with a membrane like TPO rather than shingles. Common on commercial buildings and some Florida additions.
Pitch (slope) — How steep a roof is, expressed as rise over run (e.g., 6:12). Steeper pitches cost more to work on and change which materials are suitable.
Penetration — Anything that pokes through the roof — a vent pipe, chimney, or skylight. Each penetration needs flashing or a boot to stay watertight.
R – S
Roofing Terms: R to S
Rafter — The sloped structural beam that supports the roof deck. Trusses are the modern pre-engineered version.
Ridge — The horizontal peak where two roof slopes meet at the top. A ridge vent is often installed here to exhaust hot attic air.
Secondary water barrier — An extra sealed layer over the roof deck that resists water intrusion if shingles or tiles are blown off. It’s a key credit on Florida wind-mitigation inspections.
Soffit — The underside of the roof overhang, usually vented to draw fresh air into the attic and keep the roof system cool and dry.
Square — A roofing unit equal to 100 square feet. Roofs are priced and measured in squares, so a 2,000-square-foot roof is about 20 squares.
Standing-seam metal — A premium metal roof system with raised, interlocking vertical seams and hidden fasteners. Long-lasting (40–70 years) and excellent in heat and wind — see our metal roofing page.
Starter strip — The first course of shingles installed along the eaves and rakes to seal the edges and resist wind uplift.
T – W
Roofing Terms: T to W
Tear-off — Removing the existing roof down to the decking before installing a new one. Cleaner and more reliable than laying new shingles over old.
Tile roof — Concrete or clay tiles, common in Florida for their wind performance and 40–50+ year lifespan. Learn more on our tile roofing page.
TPO — Thermoplastic polyolefin, a single-ply reflective membrane used on flat and low-slope roofs, popular on commercial buildings.
Underlayment — The water-resistant layer installed over the decking and beneath the shingles or tiles. Synthetic underlayment has largely replaced old felt paper.
Valley — The V-shaped channel where two roof slopes meet. Valleys carry a lot of water and are a common leak point, so they get extra flashing or membrane.
Ventilation — The intake-and-exhaust airflow system (soffit vents plus ridge or box vents) that keeps the attic cool and dry, extending roof life in humid climates.
Wind mitigation — A Florida inspection that documents wind-resistant roof features (roof shape, deck attachment, secondary water barrier, opening protection) to qualify for insurance premium credits. See our roof inspection page.
Wind uplift — The lifting force wind exerts on a roof. Proper fastening and starter strips resist uplift, which is why installation quality matters in storm country.
Questions, Answered
Roofing Glossary FAQ
What is a “square” in roofing?
A square equals 100 square feet of roof area. Contractors measure and price roofs in squares, so a 2,000-square-foot roof is roughly 20 squares. It’s the unit you’ll see all over your estimate.
What’s the difference between decking and underlayment?
Decking is the structural wood surface nailed to your rafters. Underlayment is the water-resistant layer installed on top of the decking, under your shingles or tiles. Both are essential to a watertight roof.
Why does flashing matter so much?
Flashing seals the transitions where water likes to sneak in — valleys, chimneys, walls, and skylights. Failed or missing flashing is one of the most common causes of roof leaks, which is why we inspect it closely.
What is wind mitigation and why do Florida homeowners care?
A wind-mitigation inspection documents the storm-resistant features of your roof so your insurer can apply premium credits. In Florida those credits can add up to real savings. Ask us about it during your inspection.
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Still Have a Roofing Term You’re Unsure About?
We’re happy to explain anything on your estimate in plain English — no pressure, no jargon. Call or request a free inspection for your Georgia or Florida home.