A.

Algae Resistance A treatment applied to roofing shingles that prevents the growth of blue-green algae, which commonly causes dark streaking on roofs in humid coastal climates like Charleston.

Asphalt Shingles The most widely used roofing material in the United States. Made from a fiberglass base coated with asphalt and mineral granules, they offer reliable protection at an affordable price point.

Attic Ventilation A system of intake and exhaust vents that allows air to circulate through your attic space, reducing heat buildup, preventing moisture damage, and extending the life of your roof.

B.

Batten Narrow strips of wood or metal installed horizontally across a roof deck that provide a nailing surface for certain roofing materials, particularly metal roofing systems.

Boot A protective flashing cover made of rubber or metal that seals around pipe penetrations where they exit through the roof surface.

C.

Cap Sheet The top layer of a built-up or modified bitumen roofing system, designed to provide the final weatherproof barrier against the elements.

Caulking A flexible sealant material used to fill gaps and joints around flashing, chimneys, vents, and other roof penetrations to prevent water infiltration.

Cricket A small, peaked construction built behind a chimney or other large roof projection to divert water and prevent pooling or ice damming in that area.

D.

Deck / Roof Deck The structural base of your roof, typically made from plywood or oriented strand board (OSB), that sits on top of the rafters and provides the surface everything else is installed onto.

Dormer A structural element that protrudes from the main roof plane, typically containing a window, adding both natural light and architectural interest to a home.

Drip Edge A metal flashing installed along the edges of a roof that directs water away from the fascia and into the gutters, protecting the underlying structure from water damage.

E.

Eave The lower edge of a roof that overhangs the exterior wall of a home. Eaves help direct water away from the foundation and can help protect siding and windows from rain.

EPDM Ethylene Propylene Diene Monomer — a synthetic rubber roofing membrane commonly used on flat or low-slope roofs due to its durability and weather resistance.

F.

Fascia The horizontal board that runs along the lower edge of the roof, capping the end of the rafters. Gutters are typically attached directly to the fascia board.

Felt Paper / Underlayment A water-resistant or waterproof barrier material installed directly onto the roof deck beneath the outer roofing material, providing an additional layer of protection.

Flashing Thin sheets of metal, typically aluminum or galvanized steel, installed at roof intersections, around chimneys, skylights, and vents to prevent water from seeping into vulnerable joints and seams.

G.

Granules The small mineral particles embedded into the surface of asphalt shingles that provide UV protection, fire resistance, and give shingles their color and texture.

Gutter A trough-shaped channel installed along the eaves of a roof that collects and directs rainwater away from the home’s foundation, siding, and landscaping.

H.

Hip Roof A roof style where all four sides slope downward toward the walls of the house. Hip roofs are common in coastal areas like Charleston due to their superior wind resistance compared to gabled roofs.

HydroStop A seamless, waterproof coating system applied to flat or low-slope roofs to prevent leaks and extend roof life without a full tear-off.

I.

Ice & Water Shield A self-adhering waterproof membrane installed in vulnerable areas of the roof such as eaves, valleys, and around penetrations to provide extra protection against water infiltration.

L.

Laminated Shingles Also known as architectural or dimensional shingles, these are multi-layered asphalt shingles that provide a more textured, dimensional appearance and greater durability than standard three-tab shingles.

Low-Slope Roof A roof with a pitch of less than 3:12, meaning it rises less than 3 inches for every 12 inches of horizontal run. These roofs require different materials and installation methods than steep-slope roofs.

M.

Metal Roofing A roofing system made from metal panels or shingles, known for exceptional longevity, energy efficiency, and wind resistance — making it an ideal choice for coastal South Carolina homes.

Modified Bitumen A type of asphalt-based roofing material reinforced with rubber or plastic modifiers, commonly used on flat and low-slope roofs for added flexibility and durability.

O.

Open Valley A roof valley where the metal flashing is left exposed rather than covered by shingles, allowing water to flow freely into the gutter system.

OSB (Oriented Strand Board) A type of engineered wood commonly used as roof decking material, made from compressed wood strands bonded with adhesive.

P.

Pitch The steepness or slope of a roof, expressed as a ratio of vertical rise to horizontal run. Pitch affects both the appearance of a home and the type of roofing materials that can be used.

Ply A single layer of roofing material. The term is commonly used to describe the number of layers in a built-up roofing system.

R.

Rafter The structural framing members that run from the ridge of the roof down to the eaves, supporting the roof deck and all materials above it.

Ridge The highest horizontal line of a roof where two opposing slopes meet at the peak.

Ridge Cap Specially shaped shingles or metal pieces installed along the ridge of a roof to provide weatherproof coverage at the peak and give the roof a finished appearance.

Ridge Vent A ventilation component installed along the entire length of a roof ridge that allows warm, moist air to escape from the attic, working in tandem with soffit vents.

S.

Sheathing Another term for the roof deck — the layer of boards or sheet material fastened to roof rafters that serves as the base for roofing materials.

Siding The exterior cladding material applied to the outer walls of a home to protect against weather and improve appearance. Common types include vinyl, fiber cement, and wood.

Slope The angle or degree of incline of a roof surface, typically expressed as rise over run (e.g., 4:12 means 4 inches of rise for every 12 inches of horizontal distance).

Soffit The underside of the roof overhang, between the fascia and the exterior wall. Soffits often contain vents that allow fresh air to enter the attic space.

Square A unit of measurement in roofing equal to 100 square feet of roof surface area. Roofing materials are typically sold and priced by the square.

Standing Seam Metal Roof A metal roofing system featuring raised interlocking seams that run vertically along the roof panels. Known for superior weather resistance, longevity, and a sleek modern appearance.

T.

Tear-Off The process of removing existing roofing materials down to the deck before installing a new roof system. A full tear-off ensures proper inspection of the deck and a clean installation surface.

Three-Tab Shingles The most basic and economical style of asphalt shingle, featuring a flat, uniform appearance with cutouts that give the appearance of three separate pieces.

TPO (Thermoplastic Polyolefin) A single-ply roofing membrane commonly used on flat and low-slope commercial roofs, known for its energy efficiency, reflectivity, and resistance to UV rays and chemicals.

U.

Underlayment A water-resistant barrier material — typically felt or synthetic — installed directly on the roof deck beneath the final roofing material as a secondary line of defense against moisture.

V.

Valley The V-shaped intersection where two roof slopes meet and channel water runoff toward the gutters. Valleys are one of the most common areas for leaks if not properly flashed.

Ventilation The system of intake and exhaust that regulates airflow through the attic and roof structure, preventing heat and moisture buildup that can damage roofing materials and increase energy costs.

W.

Wind Uplift The upward force exerted on a roof by wind pressure during storms. Coastal areas like Charleston experience significant wind uplift during hurricane season, making proper fastening and material selection critical.