InterNACHI Roofing Systems and Components 3 — Questions and Answers
Question 1: What is the primary function of drip edge flashing installed along the eaves?
- To create an air gap for ventilation under shingles
- To direct water off the roof edge into the gutter and away from the fascia (Correct answer)
- To anchor the first course of shingles
- To prevent ice from lifting the first shingle course
Correct answer: To direct water off the roof edge into the gutter and away from the fascia
Drip edge flashing guides water off the roof edge into the gutter and protects the fascia board and roof deck from water infiltration.
Question 2: Which roof covering material has the longest typical service life under normal conditions?
- 3-tab asphalt shingles
- Architectural asphalt shingles
- Wood shakes
- Slate (Correct answer)
Correct answer: Slate
Natural slate roofing can last 75–150 years or more, significantly outlasting other common residential roofing materials.
Question 3: An inspector notices that roof sheathing panels have no H-clips installed between rafters. What concern does this raise?
- Reduced fire resistance at panel seams
- Potential for panel edge sag between rafters without support (Correct answer)
- Increased risk of condensation on the deck
- Improper fastening pattern for the panels
Correct answer: Potential for panel edge sag between rafters without support
H-clips (panel clips) support sheathing panel edges between rafters to prevent sagging and maintain a flat, even deck surface.
Question 4: What does the term 'exposure' refer to when describing asphalt shingles?
- The total length of the shingle from top to bottom
- The portion of the shingle visible after installation (Correct answer)
- The number of shingle layers over the deck
- The granule color rating under UV exposure
Correct answer: The portion of the shingle visible after installation
Exposure is the portion of a shingle visible and exposed to weather after the overlapping course above is installed.
Question 5: During an inspection, a home inspector observes open valleys on an older roof. What is the recommended inspection finding?
- Open valleys are prohibited and require immediate replacement
- Open metal valleys are an acceptable roofing method that should be checked for rust and integrity (Correct answer)
- Open valleys are only acceptable on slopes greater than 6:12
- Open valleys must be sealed with roofing cement along all edges
Correct answer: Open metal valleys are an acceptable roofing method that should be checked for rust and integrity
Open metal valleys are an accepted and traditional roofing method; inspectors should assess them for corrosion, proper width, and damage rather than condemning the design.
Question 6: Which condition in an attic most directly contributes to premature deterioration of roof shingles from below?
- Insufficient insulation thickness
- Inadequate attic ventilation causing excessive heat buildup (Correct answer)
- Presence of blown-in cellulose insulation
- More than one attic access hatch
Correct answer: Inadequate attic ventilation causing excessive heat buildup
Inadequate ventilation traps heat in the attic, which bakes shingles from below, accelerating thermal cracking and reducing shingle lifespan.
Question 7: What defect is indicated when roof shingles show a pattern of missing granules in a circular or dimpled pattern?
- Manufacturer defect in granule adhesion
- Hail impact damage (Correct answer)
- Foot traffic damage
- Algae removal by pressure washing
Correct answer: Hail impact damage
Circular or dimpled granule loss patterns are characteristic of hail impact damage, which bruises the shingle mat beneath the granule layer.
InterNACHI Roofing Systems and Components 3
What is the primary function of drip edge flashing installed along the eaves?