What Does a Roof Inspector Look For

Exterior Roof Surface

The inspector begins with the primary roofing material. On asphalt shingle roofs, which cover roughly 80% of American homes, the inspector looks for curling, cracking, blistering, buckling, and granule loss. Curling occurs when shingle edges turn upward or the middle lifts away from the deck, exposing the underlayment to weather. Granule loss shows up as bald spots on shingles or as granule buildup in gutters, and it indicates that the shingle's protective coating is wearing away.

Missing shingles are obvious but not always visible from the ground, especially on the back slopes of the roof. The inspector walks or views every slope to identify gaps in coverage. Even a single missing shingle can allow water to reach the underlayment and decking within one or two rain events.

On tile roofs, the inspector checks for cracked, chipped, or displaced tiles and verifies that the underlayment beneath them is intact. On metal roofs, they look for rust, corrosion, loose or missing fasteners, and separated panel seams. On flat membrane roofs (EPDM, TPO, or PVC), they look for punctures, seam failures, blistering, and ponding water.

Flashing

Flashing is arguably the most failure-prone component on any roof. It is the metal or rubber material that seals the joints where the roof surface meets a vertical wall, chimney, vent pipe, skylight, or roof valley. The inspector examines every flashing point individually because even a small gap or lifted edge can channel water directly into the roof structure.

Chimney flashing gets particular attention because chimneys have multiple flashing components: step flashing along the sides, counter-flashing embedded in the mortar joints, and a cricket or saddle on the uphill side to divert water. Each component can fail independently. Valley flashing, which lines the channel where two roof planes meet, also receives close scrutiny because valleys concentrate large volumes of water during rain.

The inspector checks the sealant (often called roofing cement or mastic) around all flashing for cracking, shrinkage, and separation. Sealant deteriorates faster than the metal flashing itself and is a frequent source of early-stage leaks. Pipe boot flashing, the rubber collar around plumbing vent pipes, is one of the most common failure points on any roof because the rubber degrades from UV exposure and temperature cycling within 10 to 15 years.

Gutters and Drainage

The gutter system is part of the roofing system because its job is to move water off the roof and away from the building. The inspector checks gutters for proper slope toward the downspouts, visible sagging between hangers, separation from the fascia board, and accumulated debris. Clogged or poorly functioning gutters cause water to back up under the roof edge, which damages the fascia, soffit, and eventually the roof decking.

Downspouts are checked for proper attachment, adequate capacity, and effective discharge away from the foundation. The inspector notes whether downspouts empty directly at the foundation wall, which can cause basement water problems, or whether they use extensions or underground drains to carry water away from the building.

On flat roofs, the inspector evaluates the internal drains and scuppers (openings in the parapet walls) that handle drainage. Ponding water, defined as water that remains on the roof 48 hours after rain, indicates a drainage problem that accelerates membrane deterioration and adds structural load.

Attic Inspection

The attic side of the inspection is just as important as the exterior, and some inspectors argue it is more revealing. From inside the attic, the inspector can see the underside of the roof decking and detect problems that are invisible from the outside.

Moisture and water stains: Dark stains on the underside of the decking or on rafters indicate past or active leaks. The inspector uses a moisture meter to distinguish between old stains from a repaired leak and active moisture that signals an ongoing problem. Active moisture near flashing points, valleys, or penetrations confirms exactly where the leak is entering.

Daylight penetration: In a dark attic, visible pinpoints of daylight through the roof deck mean there are gaps or holes in the roofing material above. This is an immediate concern because those same gaps allow rainwater in.

Mold and mildew: Mold growth on attic framing or decking indicates chronic moisture exposure, either from a roof leak or from inadequate ventilation trapping humid air in the attic. The inspector notes the type, extent, and location of any mold to help determine whether it is a ventilation problem or a leak problem.

Structural condition: The inspector examines rafters, trusses, and the ridge beam for cracking, splitting, sagging, or signs of insect damage. Structural members that show deflection beyond normal tolerances indicate overloading, design deficiency, or deterioration that compromises the entire roof system.

Ventilation and Insulation

Proper attic ventilation requires a balanced system of intake vents (usually soffit vents) and exhaust vents (ridge vents, box vents, or gable vents). The inspector verifies that intake and exhaust vents are present, unobstructed, and properly sized for the attic space. Inadequate ventilation traps heat and moisture in the attic, which accelerates shingle aging from below, promotes mold growth, and in cold climates causes ice dams by warming the roof unevenly.

Insulation is checked for depth, coverage, and condition. Insulation that is compressed, displaced, wet, or inadequate allows heat transfer between the living space and the attic, which wastes energy and contributes to the same ventilation problems. The inspector notes whether insulation is blocking soffit vents, a common installation error that eliminates the intake airflow necessary for the ventilation system to function.

Penetrations and Roof Accessories

Every object that passes through the roof surface is a potential leak point. The inspector examines each one individually. Common penetrations include plumbing vent pipes, HVAC exhaust vents, bathroom and kitchen fan vents, electrical mast entries, satellite dish mounts, and solar panel attachment points. Each penetration has its own flashing or boot, and each one deteriorates on its own timeline.

Skylights receive special attention because they have their own flashing system, their own seals, and their own potential for condensation problems. The inspector checks the skylight frame for cracks, the flashing for separation, and the glazing for seal failure that would allow moisture between the panes.

Soffit and Fascia

The soffit (the underside of the roof overhang) and fascia (the vertical board at the roof edge) are inspected for rot, peeling paint, insect damage, and separation from the structure. Deteriorated soffit and fascia often indicate chronic moisture exposure from gutter overflow or ice damming. They also serve as entry points for animals and insects that can damage the attic and insulation.