InterNACHI - International Association of Certified Home Inspectors Roofing Systems and Components Questions and Answers — Questions and Answers
Question 1: During a roof inspection, you observe a chimney on a sloped roof that is 36 inches wide. What component should be present to properly divert water around the chimney, especially in climates with snow and ice?
- A secondary headwall flashing
- A cricket or saddle (Correct answer)
- An extra layer of underlayment
- A dedicated gutter system
Correct answer: A cricket or saddle
For chimneys wider than 30 inches, a cricket (or saddle) is required to be installed on the high side of the chimney to divert water, snow, and ice, preventing ponding and potential leaks.
Question 2: Which of the following attic ventilation systems relies on wind and natural convection (the principle that hot air rises) to function, without mechanical assistance?
- Powered attic ventilators
- Solar-powered attic fans
- Whole-house fans
- Ridge and soffit vents (Correct answer)
Correct answer: Ridge and soffit vents
Ridge and soffit vents are components of a passive ventilation system. Soffit vents act as intakes for cooler, lower air, while ridge vents serve as exhausts for hotter air that rises to the peak of the attic, creating continuous airflow without any mechanical parts.
Question 3: According to most manufacturers and building codes, what is the absolute minimum slope on which standard asphalt shingles can be installed, provided special underlayment techniques are used?
- 4:12
- 3:12
- 2:12 (Correct answer)
- 1:12
Correct answer: 2:12
The absolute minimum slope for asphalt shingle installation is 2:12 (2 inches of vertical rise for every 12 inches of horizontal run). Roofs with slopes between 2:12 and 4:12 require special application techniques, such as a double layer of underlayment, to prevent leaks from wind-driven rain and ice damming.
Question 4: A home inspector is examining a low-slope roof with a modified bitumen covering. The inspector notes several areas of 'ponding water.' According to the National Roofing Contractors Association (NRCA), ponding water is generally considered a potential issue if it remains on the roof for more than how long after a rain event?
- 12 hours
- 24 hours
- 48 hours (Correct answer)
- 72 hours
Correct answer: 48 hours
The NRCA defines ponding water as water that remains on a roof surface for more than 48 hours after rainfall, under conditions conducive to drying. Prolonged ponding can accelerate the deterioration of roofing materials.
Question 5: While inspecting the junction of a roof plane and a vertical sidewall, an inspector should look for which type of flashing to be interwoven with the shingle courses?
- Valley flashing
- Step flashing (Correct answer)
- Drip edge
- Counter-flashing
Correct answer: Step flashing
Step flashing consists of individual pieces of metal installed with each course of shingles and bent to go up the adjacent vertical wall. This method is critical for preventing water intrusion at roof-to-wall intersections.
Question 6: Which of the following is NOT a primary component that an inspector is required to inspect as part of the roofing system according to the InterNACHI Standards of Practice?
- Roof covering materials
- Gutters and downspouts
- Interior of the chimney flue (Correct answer)
- Vents, flashings, and skylights
Correct answer: Interior of the chimney flue
The InterNACHI Standards of Practice require the inspection of the visible components of the roofing system, including the roof covering, gutters, downspouts, vents, flashings, skylights, and chimneys. However, the inspector is not required to inspect the interior of flues or chimneys.
During a roof inspection, you observe a chimney on a sloped roof that is 36 inches wide.
What component should be present to properly divert water around the chimney, especially in climates with snow and ice?