NHIE Roofing 3 — Questions and Answers
Question 1: A home inspector finds granule loss concentrated in streaks running down asphalt shingles. The most likely cause is:
- Foot traffic damage from prior roof work (Correct answer)
- Normal weathering from UV exposure
- Manufacturer defect in granule adhesion
- Hail impact along the strike zone
Correct answer: Foot traffic damage from prior roof work
Streaking granule loss typically follows foot traffic patterns where installers or maintenance workers have walked on the roof, abrading the granule surface.
Question 2: What is the minimum slope generally required for standard 3-tab asphalt shingles without special low-slope installation procedures?
- 2:12
- 3:12 (Correct answer)
- 4:12
- 6:12
Correct answer: 3:12
Most manufacturers require at least a 3:12 slope for standard asphalt shingle installation; slopes below this need special underlayment and double-coverage methods.
Question 3: Which underlayment material provides the best water-resistant barrier under slate or tile roofing?
- 15-lb felt paper
- 30-lb felt paper
- Self-adhering modified bitumen membrane (Correct answer)
- Housewrap installed horizontally
Correct answer: Self-adhering modified bitumen membrane
Self-adhering modified bitumen (peel-and-stick) membranes provide a superior secondary waterproof barrier appropriate under heavy roofing materials with long service lives.
Question 4: Step flashing is used where:
- A sloped roof meets a vertical wall (Correct answer)
- Two roof planes meet at a ridge
- Flat roofing abuts a parapet wall at grade
- Skylight curbs are sealed at the sill
Correct answer: A sloped roof meets a vertical wall
Step flashing consists of individual L-shaped metal pieces installed one per shingle course where a sloped roof intersects a vertical wall.
Question 5: During a roof inspection, the inspector notes the wood decking feels spongy underfoot near the eaves. This most likely indicates:
- Rot from chronic moisture intrusion or ice damming (Correct answer)
- Inadequate nailing of the roof deck panels
- Structural rafter spacing that is too wide
- Thermal expansion of OSB panels in summer heat
Correct answer: Rot from chronic moisture intrusion or ice damming
Spongy decking near eaves strongly suggests wood rot caused by repeated wetting from ice dams, inadequate ventilation, or long-term leak infiltration.
Question 6: What does the term 'exposure' mean when applied to asphalt shingles?
- The portion of each shingle visible after the next course is laid (Correct answer)
- The total surface area of one shingle square
- The distance from the eave to the ridge
- The number of layers of shingles on the roof
Correct answer: The portion of each shingle visible after the next course is laid
Exposure is the weather-exposed portion of a shingle, measured from the bottom edge of one shingle to the bottom edge of the shingle in the course above it.
Question 7: An inspector sees moss growth covering significant areas of an asphalt shingle roof. The main structural concern is:
- Moss roots lifting shingles and retaining moisture that accelerates decay (Correct answer)
- Increased roof weight causing structural overload
- Moss blocking ridge vents and reducing attic ventilation
- Discoloration reducing property value without physical damage
Correct answer: Moss roots lifting shingles and retaining moisture that accelerates decay
Moss rhizoids penetrate shingle surfaces, physically lifting and separating granules while retaining moisture that accelerates shingle and deck deterioration.
NHIE Roofing 3
A home inspector finds granule loss concentrated in streaks running down asphalt shingles.
The most likely cause is: