You do not need a construction degree to understand your roof. But knowing the basic parts helps you communicate with contractors, understand estimates, and recognize problems before they become expensive. Here is every major component of a residential roof, explained in plain English.
The Structure (What Holds Everything Up)
Rafters/Trusses
The skeleton of your roof. Rafters are individual beams cut and assembled on-site. Trusses are pre-engineered triangular frames built in a factory. Most Savannah homes built after 1970 use trusses.
Decking (Sheathing)
Plywood or OSB panels nailed to the rafters/trusses, creating the flat surface that everything else is attached to. This is what we inspect during tear-off — rotted decking must be replaced before new roofing goes on.
The Waterproofing Layers
Ice and Water Shield
A self-adhering waterproof membrane applied at the most vulnerable points: valleys, eaves, and around all penetrations. It seals around nails that penetrate through it, creating a watertight backup layer.
Underlayment
A sheet material laid across the entire deck before shingles are installed. Modern synthetic underlayment is stronger and lays flatter than old-style felt paper. This is your secondary waterproofing if a shingle fails or lifts.
The Shingle System
Starter Strip
A special adhesive-backed strip along the eaves and rakes. The starter strip seals the first row of shingles and prevents wind from lifting them at the edges.
Field Shingles
The shingles that cover the main expanse of the roof. Installed in overlapping rows from bottom to top, with staggered offsets to prevent water channeling through seams.
Ridge Cap
Specially shaped shingles that straddle the ridge (peak) and hips of the roof. They seal the highest and most wind-exposed points. Premium ridge caps are thicker and more wind-resistant than economy versions.
Metal Components
Drip Edge
Metal strips along the eaves and rakes that direct water away from the fascia board into the gutters. Required by Georgia building code on all new roof installations.
Flashing
Metal installed wherever the roof meets a wall, chimney, skylight, or changes direction. Flashing failure is one of the top causes of roof leaks. See our flashing repair guide.
Vent Boots
Rubber collars that seal around plumbing vent pipes. These degrade in Savannah's heat and UV exposure, making them a common source of leaks. See our vent boot repair guide.
Ventilation
Ridge Vent
Runs along the peak of the roof, allowing hot air to escape from the attic. Works in conjunction with soffit vents to create natural airflow.
Soffit Vents
Located in the eaves (underside of the roof overhang). They allow cool air to enter the attic, pushing hot air upward toward the ridge vent.
Why This Matters for Your Estimate
When you get a roofing estimate, every one of these components should be listed. If an estimate just says "install new roof" with no mention of underlayment type, ice and water shield, drip edge, or starter strip, that is a red flag. A proper estimate specifies every layer.
Questions about your roof's components? Schedule a free inspection and we will walk you through your roof in person, explaining exactly what shape each component is in.
