InterNACHI Roof Inspector flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Square of roofing

A unit of roof area equal to 100 square feet. Material quantities, labor estimates, and shingle bundles are commonly calculated in squares.

3-tab shingle exposure

Standard 3-tab asphalt strips are 36 inches long with a nominal 12-inch exposure, producing three tabs per strip and a relatively flat, uniform roof surface.

Architectural shingle

A laminated asphalt shingle made of two plies, thicker and heavier than 3-tab, with a dimensional appearance and typically longer manufacturer warranty periods.

Underlayment purpose

A secondary barrier beneath the roof covering that sheds water reaching the deck and protects the structure before and during covering installation.

Drip edge function

Metal flashing at the eaves and rakes that directs water away from the fascia and deck edge, helping prevent rot and fascia staining.

Step flashing

L-shaped metal pieces installed in courses along a roof-to-wall intersection, interleaved with roofing, to keep water from entering the sidewall joint.

Standing seam metal roof

Metal panels joined by raised seams with concealed fasteners, offering good water resistance and commonly permitted on lower slopes than through-fastened panels.

Wood shake versus shingle

Shakes are split along the grain and thicker; shingles are sawn and thinner. Both require appropriate sheathing and minimum slope for performance.

Fall protection threshold

OSHA generally requires fall protection for construction work at 6 feet or more above a lower level, using guardrails, nets, or personal fall-arrest systems.

Ladder 4:1 rule

For every 4 feet of working height, the ladder base should be 1 foot from the wall, with the top extending at least 3 feet above the landing.

Ladder duty rating

The maximum working load a ladder is designed to support, from Type III at 200 pounds through Type IAA at 375 pounds, including the user and tools.

Three-point contact

Maintaining two hands and one foot, or two feet and one hand, on the ladder at all times to reduce the chance of a fall.

Roof walk optional

Most standards of practice do not require the inspector to walk the roof; alternative methods may be used when conditions are unsafe.

Steep-slope walking limit

Roofs steeper than about 6:12 are commonly considered unsafe to walk without specialized equipment such as roof harnesses and anchors.

Power line clearance

Ladders and long tools should be kept at least 10 feet from energized overhead lines to avoid contact and electrocution.

Skylight fall hazard

Skylights and plastic domes can be fragile and should never be stepped on; treat them as openings and route around them.

Granule loss

Bare patches or granules collecting in gutters indicate shingle wear from age, traffic, hail, or defects, and signal reduced remaining service life.

Hail bruising

Random, soft, dark spots on asphalt shingles where granules are displaced; pressing may reveal a soft spot, distinguishing it from blisters or mechanical damage.

Wind uplift damage

Missing tabs, creased or torn shingles, and lifted edges caused by wind, often where sealant strips have failed or edges are unsealed.

Kick-out flashing

A small flashing piece at the bottom of a roof-to-wall intersection that diverts water away from the wall and prevents concentrated leakage.

Ice dam

A ridge of ice at the eaves formed when melted snow refreezes, trapping water that can back up under shingles and cause interior leaks.

Attic ventilation ratio

A common rule of about 1 square foot of net free ventilation per 150 square feet of attic floor, balanced between intake and exhaust vents.

Ponding water

Standing water on a low-slope roof that remains 48 hours or more after rain, indicating inadequate drainage or slope and risking membrane deterioration.

Algae streaking

Dark streaks on asphalt roofs caused by Gloeocapsa magma, a moisture-loving organism that is largely cosmetic but can indicate persistent dampness.

Sagging roof line

A visible dip in the ridge or rafter line that suggests framing, sheathing, or structural problems needing further evaluation by a qualified specialist.

Inspection method disclosure

The report should state how the roof was inspected, such as walked, viewed from eaves, binoculars, or drone, along with any areas not accessed.

Standards of practice scope

The defined minimum inspection requirements describing what the inspector must observe and report, and which conditions are excluded or limited.

Life-expectancy disclaimer

Inspectors generally are not required to predict remaining roof life; reports may recommend evaluation by a roofing specialist instead.

Condition-based language

Using terms such as observed, appears, and not visible to describe conditions factually without asserting causation, cost, or code compliance.

Photograph documentation

Dated, labeled images referenced in the report narrative, combining wide context shots with close-ups of defects to support observations.

Concealed component limitation

Components hidden beneath the roof covering, such as underlayment and flashing, cannot be fully inspected and should be disclosed as limitations.

Report structure

A consistent format of description, observations, limitations, and recommendations that helps clients understand conditions and appropriate next steps.