InterNACHI Certified Home Inspector Exam — Questions and Answers

Question 1: During a home inspection, the inspector notices that the double top plate on a load-bearing wall has a large splice in both plates directly above a door opening. What is the structural concern?

Top plate splices are only acceptable in non-load-bearing walls
The splice indicates the wrong nail pattern was used during framing
Splices directly over openings weaken the top plate where load transfer is most critical (Correct answer)
The splice creates a visible seam that affects the drywall finish

Correct answer: Splices directly over openings weaken the top plate where load transfer is most critical

Top plate splices must be offset from each other and from openings; splices directly over headers interrupt the load path at a critical transfer point.

Question 2: A home inspector finds a window that has a broken seal, evidenced by fogging between the panes. What component has failed?

The window latch hardware
The interior weatherstripping
The insulated glass unit (IGU) (Correct answer)
The window frame

Correct answer: The insulated glass unit (IGU)

Fogging between panes indicates seal failure of the insulated glass unit (IGU), which allows moist air to enter and condense between the glass layers.

Question 3: When inspecting a service entrance, what does the inspector look for at the weatherhead?

Proper fusing of all three service conductors
A disconnect within 3 feet of the meter
A minimum of four conductors entering the home
Adequate drip loop to prevent water from entering the conduit (Correct answer)

Correct answer: Adequate drip loop to prevent water from entering the conduit

A drip loop is essential at the weatherhead to ensure rainwater drips off the conductors before reaching the entry point rather than running into the conduit.

Question 4: What is the primary purpose of an equipment grounding conductor (EGC) in a branch circuit?

To reduce electromagnetic interference in the circuit
To provide a low-impedance fault path back to the source (Correct answer)
To balance the load between hot and neutral conductors
To carry the return current of normal circuit operation

Correct answer: To provide a low-impedance fault path back to the source

The EGC provides a low-impedance path for fault current so that overcurrent devices trip quickly and safely during a ground fault.

Question 5: What is the purpose of an 'energy recovery ventilator' (ERV) compared to a standard heat recovery ventilator (HRV)?

ERVs recover both heat and moisture from exhaust air; HRVs recover heat only (Correct answer)
ERVs use electric resistance heating to temper incoming air; HRVs use heat exchange only
ERVs are designed for cooling climates only; HRVs are for heating climates only
ERVs exhaust more air than they supply; HRVs maintain balanced airflow

Correct answer: ERVs recover both heat and moisture from exhaust air; HRVs recover heat only

An ERV transfers both sensible heat and moisture (latent energy) between incoming and outgoing air streams, while an HRV transfers only sensible heat.

Question 6: What is a common plumbing issue in homes?

Well-maintained faucets.
Pipe leaks (Correct answer)
Properly working HVAC.
Unclogged pipes.

Correct answer: Pipe leaks

Pipe leaks are one of the most prevalent and damaging plumbing issues homeowners face. They can occur due to corrosion, high water pressure, freezing, or damaged seals, leading to water damage, mold growth, and increased water bills. Early detection and repair of leaks are crucial to prevent more extensive and costly problems.

Question 7: 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?

Drip edge
Valley flashing
Step flashing (Correct answer)
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 8: Which HVAC filter rating system measures a filter's ability to capture particles of specific sizes?

MERV rating (Correct answer)
AFUE rating
EER rating
SEER rating

Correct answer: MERV rating

MERV (Minimum Efficiency Reporting Value) rates filter efficiency from 1–16 based on the percentage of particles captured at different sizes.

Question 9: During an inspection of a home built in 1988, an inspector identifies flexible, gray plastic water supply pipes stamped with "PB2110." This piping material is known as:

Chlorinated polyvinyl chloride (CPVC)
Acrylonitrile butadiene styrene (ABS)
Polybutylene (PB) (Correct answer)
Cross-linked polyethylene (PEX)

Correct answer: Polybutylene (PB)

Polybutylene (PB) is a type of plastic piping, often gray and marked with the code "PB2110," that was used extensively from the late 1970s to the mid-1990s. It is known to degrade when exposed to oxidants in public water supplies, becoming brittle and failing without warning, which led to class-action lawsuits and its removal from building codes.

Question 10: What does the 'net free area' of a vent refer to?

The attic floor area divided by the ventilation ratio
The actual open area through which air can pass, excluding frame and screen (Correct answer)
The total face area of the vent cover
The required ventilation area minus existing ventilation already installed

Correct answer: The actual open area through which air can pass, excluding frame and screen

Net free area is the actual unobstructed opening through which air flows, which is always less than the gross vent dimensions due to frames, louvers, and screens.

Question 11: Which interior finish material is most commonly used as a tile backer in wet areas and is resistant to moisture damage?

Cement board (cementitious backer unit) (Correct answer)
Standard drywall (gypsum board)
Plywood sheathing
Oriented strand board (OSB)

Correct answer: Cement board (cementitious backer unit)

Cement board (cementitious backer unit) is the preferred tile substrate in wet areas because it does not swell, deteriorate, or support mold growth when exposed to moisture.

Question 12: Which condition indicates a failed wax ring seal beneath a toilet?

The toilet flushes slowly
The tank refills loudly after flushing
Water stains or soft flooring around the toilet base (Correct answer)
The toilet rocks slightly side to side

Correct answer: Water stains or soft flooring around the toilet base

Water stains, soft flooring, or odors around the toilet base indicate a failed wax ring allowing sewer gases and water to escape.

Question 13: What is a 'p-trap' designed to do?

Regulate water pressure at fixtures
Prevent backflow in the water supply
Hold water to block sewer gases from entering the home (Correct answer)
Filter debris from drain lines

Correct answer: Hold water to block sewer gases from entering the home

A p-trap holds a water seal that blocks sewer gases and vermin from entering the living space through the drain opening.

Question 14: During an exterior inspection, you observe a second-story deck where the wooden support posts are in direct contact with the soil at their base. What is the PRIMARY concern you should report to your client?

The soil contact may violate local zoning ordinances.
The deck posts are likely not the correct species of wood.
The deck is not aesthetically pleasing.
The wood is susceptible to rot and wood-destroying insect infestation. (Correct answer)

Correct answer: The wood is susceptible to rot and wood-destroying insect infestation.

Direct wood-to-soil contact creates a pathway for moisture to wick into the wood, which accelerates decay and makes it highly vulnerable to wood-destroying insects like termites. This condition compromises the structural integrity of the posts and, consequently, the safety of the entire deck structure.

Question 15: Why should HVAC ducts be regularly cleaned?

To improve air quality and system efficiency (Correct answer)
To maintain aesthetic value.
To reduce energy costs.
To increase energy consumption.

Correct answer: To improve air quality and system efficiency

Regular cleaning of HVAC ducts is essential for maintaining a healthy indoor environment and optimizing system performance. Over time, dust, allergens, and other contaminants accumulate in ducts, which can then be circulated throughout the home, negatively impacting air quality and potentially triggering allergies or respiratory issues. Clean ducts also allow the HVAC system to operate more efficiently, reducing energy consumption and extending its lifespan.

Question 16: Which of the following best describes the function of a whole-house surge protector installed at the main electrical panel?

It diverts excess voltage from transient surges to protect connected devices (Correct answer)
It monitors amperage draw and shuts off power during overloads
It replaces the need for GFCI and AFCI protection
It prevents all circuit breakers from tripping during power surges

Correct answer: It diverts excess voltage from transient surges to protect connected devices

A whole-house surge protector diverts excess transient voltage to ground, reducing the risk of surge damage to sensitive electronics throughout the home.

Question 17: A home inspector finds that junction box covers are missing throughout the home. What hazard does this present?

It is only a concern in bathrooms and kitchens
It reduces the ampacity of the circuits by increasing heat dissipation
It allows moisture to enter the wiring, causing corrosion
It exposes live wire connections and increases the risk of shock or arc faults (Correct answer)

Correct answer: It exposes live wire connections and increases the risk of shock or arc faults

Open junction boxes expose energized wire splices to accidental contact, creating shock and arc flash hazards for occupants.

Question 18: 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?

2:12 (Correct answer)
4:12
3:12
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 19: Which safety control shuts down a gas furnace when the heat exchanger overheats?

Flame sensor
Draft inducer relay
Limit switch (high-limit control) (Correct answer)
Pressure switch

Correct answer: Limit switch (high-limit control)

The limit switch monitors heat exchanger temperature and shuts off the burners if the temperature exceeds a safe threshold, preventing overheating and potential fires.

Question 20: What is the primary purpose of ice and water shield underlayment installed at roof eaves?

To provide a slip-resistant surface for roofing installers
To prevent water infiltration caused by ice dams backing up under shingles (Correct answer)
To add an additional layer of thermal insulation at the cold eave edge
To increase the fire resistance rating of the roof assembly

Correct answer: To prevent water infiltration caused by ice dams backing up under shingles

Ice and water shield is a self-adhering, waterproof membrane installed at eaves to prevent water from ice dams from wicking back under shingles and into the structure.

Question 21: What does the term 'live load' refer to in structural engineering for residential buildings?

Temporary or variable loads such as occupants, furniture, and snow (Correct answer)
Loads from electrical wiring and plumbing
The weight of the structure itself
Loads that cause vibration in the floor system

Correct answer: Temporary or variable loads such as occupants, furniture, and snow

Live loads are variable, temporary loads including people, furniture, and snow that a structure must support in addition to its own permanent weight (dead load).

Question 22: During a home inspection, the inspector turns on multiple fixtures simultaneously and notices a dramatic drop in water pressure. This suggests:

A faulty pressure-reducing valve
Inadequate pipe size, a partially closed valve, or significant pipe corrosion restricting flow (Correct answer)
The water meter is undersized
Normal behavior in all homes

Correct answer: Inadequate pipe size, a partially closed valve, or significant pipe corrosion restricting flow

A significant pressure drop under simultaneous demand points to undersized supply piping, obstruction, or a partially closed main valve restricting flow.

Question 23: What type of electrical hazard is indicated by scorch marks or discoloration around an outlet or switch cover plate?

Evidence of arcing or overheating at that device (Correct answer)
Indication of reversed polarity only
Overloaded neutral conductor
Normal aging of plastic outlet covers

Correct answer: Evidence of arcing or overheating at that device

Scorch marks or discoloration around electrical devices indicate past or ongoing arcing or heat buildup, which is a serious fire hazard.

Question 24: A home inspector observes that a flat roof has significant ponding water 48 hours after rainfall. What is the concern?

Ponding indicates the roof was recently re-coated
Ponding only becomes a deficiency if it exceeds 2 inches in depth
Ponding can accelerate membrane deterioration and indicates inadequate drainage (Correct answer)
Ponding is expected and not a deficiency on flat roofs

Correct answer: Ponding can accelerate membrane deterioration and indicates inadequate drainage

Ponding water that remains 48 hours after rainfall accelerates membrane degradation and indicates poor slope or blocked drainage, both of which are reportable deficiencies.

Question 25: Which of the following materials is commonly used for drain, waste, and vent (DWV) piping in modern residential construction?

ABS or PVC plastic (Correct answer)
Cast iron only
Copper type M
Galvanized steel

Correct answer: ABS or PVC plastic

ABS (acrylonitrile butadiene styrene) and PVC (polyvinyl chloride) are the most common materials used for DWV systems in modern residential construction.

Question 26: When inspecting a crawl space with a ground vapor barrier, what deficiency should an inspector note if the barrier is not sealed at the perimeter walls?

Unsealed edges allow pest entry under the barrier
The barrier is a fire hazard without perimeter attachment
Moisture will migrate from exposed soil edges into the crawl space air (Correct answer)
The barrier will not reduce radon entry from soil gases

Correct answer: Moisture will migrate from exposed soil edges into the crawl space air

Ground vapor barriers must be sealed or lapped up the foundation walls to prevent soil moisture from evaporating around the edges and entering the crawl space.

Question 27: What is the purpose of a backflow preventer on a hose bibb (exterior faucet)?

To filter sediment from outdoor water
To regulate water pressure at the outlet
To shut off flow automatically in freezing conditions
To prevent contaminated water from siphoning back into the potable supply (Correct answer)

Correct answer: To prevent contaminated water from siphoning back into the potable supply

A backflow preventer (vacuum breaker) stops contaminated water — such as from a garden hose left in a chemical solution — from being siphoned back into the home's potable water supply.

Question 28: What does the term 'cripple wall' refer to in residential construction?

A non-load-bearing partition wall
A wall with a damaged load-bearing member
A short wood-framed wall between the foundation and the first floor (Correct answer)
A wall constructed with substandard materials

Correct answer: A short wood-framed wall between the foundation and the first floor

A cripple wall is a short wood-framed stud wall built on top of the foundation that raises the first floor above grade level.

Question 29: An inspector is examining the interior of an attached garage and notes that the entry door leading into the house is a standard, hollow-core interior door. Why is this a significant defect?

The door is not properly sealed to prevent vehicle exhaust fumes from entering the home.
Hollow-core doors are not insulated, leading to significant energy loss.
The door provides inadequate security against forced entry from the garage.
The door lacks the required fire-resistance rating to slow the spread of a fire from the garage to the living space. (Correct answer)

Correct answer: The door lacks the required fire-resistance rating to slow the spread of a fire from the garage to the living space.

The door between an attached garage and the living area is part of the fire separation. Building codes require this door to be a solid wood door at least 1-3/8 inches thick, a solid or honeycomb-core steel door of the same thickness, or a door with a minimum 20-minute fire rating. A hollow-core door offers minimal fire resistance and is a serious safety hazard.

Question 30: What is a common sign of structural damage?

No visible damage.
Visible cracks or misaligned doors (Correct answer)
Properly functioning HVAC.
Aesthetically pleasing paint.

Correct answer: Visible cracks or misaligned doors

Structural damage often manifests as visible signs such as wide, jagged, or horizontal cracks in foundations, walls, or ceilings. Other key indicators include doors and windows that stick or are misaligned, sloping or uneven floors, or bowing walls, all of which suggest potential issues with the building's load-bearing components and overall stability.

Question 31: Which document is typically provided after a home inspection?

Inspection report (Correct answer)
Property value report.
Warranty document.
Inspection certificate.

Correct answer: Inspection report

Following a home inspection, the inspector compiles a comprehensive inspection report. This detailed document outlines all findings, including descriptions of the property's condition, identified defects, safety concerns, and recommendations for maintenance or further evaluation. It serves as a critical reference for the client, informing their decisions regarding the property.

Question 32: 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?

72 hours
24 hours
48 hours (Correct answer)
12 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 33: An inspector discovers a sealed attic hatch that has never been opened. Under InterNACHI standards, what is the correct action?

Note the limitation and inspect as much of the attic as is accessible (Correct answer)
Force the hatch open as required by the standards
Recommend the client hire a contractor to unseal the hatch before closing
Skip the attic inspection entirely

Correct answer: Note the limitation and inspect as much of the attic as is accessible

Inspectors should note limitations to access and inspect whatever portions of the attic are accessible without causing damage.

Question 34: Which roofing defect is described as a separation of the laminate layers in an architectural (dimensional) shingle?

Checking
Alligatoring
Delamination (Correct answer)
Granule bridging

Correct answer: Delamination

Delamination in architectural shingles refers to the separation of the top and bottom laminated layers, which compromises the shingle's integrity and weather resistance.

Question 35: An InterNACHI inspector finds the main electrical panel cover is secured with stripped screws. What should the inspector do?

Note the condition and report whether or not the panel was inspected (Correct answer)
Recommend the client hire an electrician to open the panel
Skip the panel inspection and note it is inaccessible
Remove the cover using whatever means necessary to complete the inspection

Correct answer: Note the condition and report whether or not the panel was inspected

The inspector should report the condition and clearly state whether the panel was inspected or not, since obstruction limits the inspection scope.

Question 36: An inspector notices that roof sheathing panels have no H-clips installed between rafters. What concern does this raise?

Increased risk of condensation on the deck
Reduced fire resistance at panel seams
Potential for panel edge sag between rafters without support (Correct answer)
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 37: An inspector notes that an exterior receptacle cover closes tightly only when no plug is inserted. Which type of cover should be installed instead?

Standard flat plate cover rated for outdoor use
GFCI receptacle with a standard flat cover
Extension cord rated for outdoor use
Bubble cover (in-use weatherproof cover) that protects plugged-in cords (Correct answer)

Correct answer: Bubble cover (in-use weatherproof cover) that protects plugged-in cords

In-use weatherproof covers (bubble covers) maintain protection when cords are plugged in, which is required for all new outdoor receptacle installations.

Question 38: A home inspector notices the condensate drain line on an air handler is dripping water at the connection joint. What should be reported?

The evaporator coil is frozen
Normal condensation, no action needed
Improper drain line installation or joint failure requiring repair (Correct answer)
The unit is low on refrigerant

Correct answer: Improper drain line installation or joint failure requiring repair

A leaking condensate drain joint indicates a failed or improperly installed connection that can cause water damage and should be repaired by a qualified technician.

Question 39: What is the maximum height above the floor at which a standard wall-mounted electrical outlet may be installed per general accessibility guidelines?

No maximum is specified in the NEC (Correct answer)
48 inches
18 inches
36 inches

Correct answer: No maximum is specified in the NEC

The NEC does not specify a maximum height for receptacle installation, though accessibility guidelines (ADA) recommend no higher than 48 inches.

Question 40: What is the primary safety concern when a home inspector discovers aluminum branch circuit wiring connected to a standard copper-rated outlet?

Aluminum wiring is not approved for residential use under any code
Aluminum corrodes faster in humid climates
Aluminum wiring cannot carry sufficient amperage
Aluminum expands and contracts differently than copper, causing loose connections and fire risk (Correct answer)

Correct answer: Aluminum expands and contracts differently than copper, causing loose connections and fire risk

Aluminum expands and contracts at a different rate than copper, causing connections to loosen over time, creating heat and fire hazards.

Question 41: An inspector observes that a wood girder in a crawl space shows significant end decay where it enters a masonry pocket. What is the most likely cause?

Chemical reaction with concrete
Overloading of the beam
Insect damage from below
Trapped moisture from condensation or water intrusion in the masonry pocket (Correct answer)

Correct answer: Trapped moisture from condensation or water intrusion in the masonry pocket

Masonry pockets trap moisture around beam ends because they lack ventilation and drainage, creating consistently wet conditions that promote wood decay fungi.

Question 42: What is the primary concern of electrical systems in home inspections?

Efficiency of appliances.
Safety and code compliance (Correct answer)
Electrical consumption rates.
Aesthetic appeal.

Correct answer: Safety and code compliance

The paramount concern when inspecting electrical systems is ensuring the safety of the occupants and compliance with current electrical codes. Inspectors look for hazards like improper wiring, overloaded circuits, lack of grounding, and outdated components that could lead to electrical fires, shocks, or system failures. Aesthetic appeal or consumption rates are secondary to safety.

Question 43: Which wire color in a standard 120V household circuit indicates the neutral conductor?

White (Correct answer)
Black
Green
Red

Correct answer: White

White wires are the neutral conductors in standard 120V household circuits, carrying current back to the panel.

Question 44: When inspecting a heat pump, what does it mean when the outdoor unit is running but the indoor air handler is blowing cool — not warm — air in heating mode?

The thermostat is set incorrectly to 'cool'
The system is in defrost cycle and will recover shortly
The filter is excessively dirty
The reversing valve may be stuck in cooling mode (Correct answer)

Correct answer: The reversing valve may be stuck in cooling mode

The reversing valve switches refrigerant flow direction to provide heating; if stuck in the cooling position, the system cools rather than heats even with the thermostat calling for heat.

Question 45: An inspector is examining the refrigerant lines connected to an outdoor condenser unit. One line is larger in diameter, insulated, and feels cool to the touch while the system is operating in cooling mode. This line is known as the:

Liquid line
Condensate line
Discharge line
Suction line (Correct answer)

Correct answer: Suction line

The larger, insulated copper line is the suction line (or vapor line). It carries cool, low-pressure refrigerant in a gaseous state from the indoor evaporator coil back to the outdoor compressor. It is insulated to prevent it from absorbing excess heat from the ambient air, which would decrease the system's efficiency.

Question 46: What does 'service ampacity' refer to when a home inspector evaluates an electrical service?

The total wattage of all appliances connected to the panel
The voltage rating of the utility transformer supplying the home
The number of circuit breaker slots available in the panel
The maximum current the service entrance conductors and main breaker are rated to carry (Correct answer)

Correct answer: The maximum current the service entrance conductors and main breaker are rated to carry

Service ampacity is the rated capacity of the service entrance conductors and main overcurrent protection, commonly 100A, 150A, or 200A for residential homes.

Question 47: When inspecting a metal roof, an inspector notices white, powdery deposits near fasteners. What does this indicate?

Condensation freeze-thaw cycling under the panels
Galvanic corrosion from dissimilar metals in contact (Correct answer)
Efflorescence from the underlying concrete deck
Normal oxidation of the metal surface coating

Correct answer: Galvanic corrosion from dissimilar metals in contact

White powdery deposits near fasteners typically indicate galvanic corrosion, which occurs when dissimilar metals are in contact in the presence of moisture.

Question 48: What condition is indicated when a home inspector tests a GFCI outlet and the reset button does not pop out after pressing the test button?

The GFCI requires a 20-amp circuit to function properly
The GFCI is functioning correctly and does not need to trip
The GFCI is wired in reverse polarity
The GFCI device has failed and is no longer providing protection (Correct answer)

Correct answer: The GFCI device has failed and is no longer providing protection

If pressing the test button on a GFCI does not cause the reset button to pop out and interrupt power, the device has failed and must be replaced.

Question 49: What is the R-value per inch for closed-cell spray polyurethane foam insulation?

R-2 per inch
R-3.5 per inch
R-10 per inch
R-6 to R-7 per inch (Correct answer)

Correct answer: R-6 to R-7 per inch

Closed-cell spray polyurethane foam typically provides R-6 to R-7 per inch, the highest R-value per inch among commonly used insulation types.

Question 50: What condition at a chimney cricket (saddle) should an inspector flag as a deficiency?

Cricket slope is steeper than the main roof
Cricket is wider than the chimney
Cricket flashing is not sealed or is pulling away from the chimney (Correct answer)
Cricket is constructed of metal

Correct answer: Cricket flashing is not sealed or is pulling away from the chimney

Unsealed or separated cricket flashing allows water to penetrate at the junction between the chimney and roof, a common leak point.

Question 51: When examining exterior trim, which condition is most indicative of long-term water damage rather than recent or cosmetic damage?

Soft, spongy wood that probes easily with a screwdriver (Correct answer)
Dirt accumulation in crevices
Surface paint cracking
Faded stain on trim boards

Correct answer: Soft, spongy wood that probes easily with a screwdriver

Wood that is soft and easily penetrated by a probe tool indicates advanced decay where structural integrity of the trim or underlying framing may be compromised.

Question 52: Which of the following panels is commonly flagged by home inspectors due to recalled breakers and a history of fires?

Siemens ITE
Square D QO series
Cutler-Hammer panels
Zinsco (Sylvania) panels (Correct answer)

Correct answer: Zinsco (Sylvania) panels

Zinsco (also sold as Sylvania) panels have been documented to have breakers that weld shut and fail to trip, posing a significant fire hazard.

Question 53: What is the typical temperature range at which a residential water heater thermostat should be set to balance scalding prevention and Legionella control?

115–120°F
150–160°F
120–140°F (Correct answer)
100–110°F

Correct answer: 120–140°F

The recommended range is 120–140°F; 120°F minimizes scalding risk for most households, while 140°F is advised where Legionella is a concern — with an anti-scald mixing valve at fixtures.

Question 54: You are inspecting a timber retaining wall that is 5 feet tall and located 3 feet from the home's foundation. The wall is leaning noticeably outward and has several rotting timbers at its base. According to the Standards of Practice, what is your responsibility?

To perform a structural analysis of the soil pressure behind the wall.
To ignore the wall as it is a landscaping feature.
To provide a cost estimate for replacing the wall.
To report the wall's condition as a material defect that could adversely affect the home. (Correct answer)

Correct answer: To report the wall's condition as a material defect that could adversely affect the home.

The InterNACHI Standards of Practice require an inspector to report on retaining walls that are likely to adversely affect the building. A tall, leaning, and rotting wall in close proximity to the foundation presents a clear risk of failure, which could impact the home's structure. This must be reported as a material defect. Inspectors are not required to provide cost estimates or perform engineering analyses.

Question 55: 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?

Vents, flashings, and skylights
Interior of the chimney flue (Correct answer)
Gutters and downspouts
Roof covering materials

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.

Question 56: During an exterior inspection, which window condition requires reporting as a deficiency?

Missing or damaged glazing compound (putty) around glass (Correct answer)
Aluminum frame oxidation
Single-pane glass in a temperate climate
Painted-shut interior storm window

Correct answer: Missing or damaged glazing compound (putty) around glass

Missing or damaged glazing compound allows water to seep between the glass and frame, leading to rot and water intrusion.

Question 57: Which of the following is the correct InterNACHI-recommended finding when a home inspector observes a 60-amp main disconnect in a home with central air conditioning and electric range?

The service capacity appears insufficient for the electrical loads present and evaluation by an electrician is recommended (Correct answer)
60-amp service is acceptable if no additions have been made
60-amp service is adequate for any modern home
This only needs reporting if the panel is over 40 years old

Correct answer: The service capacity appears insufficient for the electrical loads present and evaluation by an electrician is recommended

Modern homes with central AC and electric cooking typically require 150–200 amp service; 60-amp service is likely undersized and warrants an electrician's evaluation.

Question 58: A home inspector observes popcorn (acoustical) ceiling texture applied prior to 1980. What additional concern should be noted?

The texture is a fire hazard due to its porous nature
The texture may hide water damage
The texture reduces room acoustics significantly
The texture may contain asbestos and should be tested before disturbance (Correct answer)

Correct answer: The texture may contain asbestos and should be tested before disturbance

Popcorn ceiling textures applied before approximately 1978–1980 may contain asbestos, which poses a health hazard if disturbed; testing is recommended prior to any renovation.

Question 59: An inspector observes a service entrance cable with damaged outer insulation at the weatherhead. What is the primary concern?

Water intrusion causing corrosion inside the meter base (Correct answer)
The utility company will disconnect service automatically
Reduced amperage capacity of the service
Damaged insulation affects only aesthetics

Correct answer: Water intrusion causing corrosion inside the meter base

Damaged service entrance cable insulation allows moisture to enter the cable and meter base, causing corrosion and potential arcing failures.

Question 60: A home inspector finds that bathroom exhaust fans are ducted into the attic and terminate without an outlet. What deficiency does this represent?

Moisture-laden air is being discharged into the attic, promoting mold and rot (Correct answer)
Insufficient CFM rating for the bathroom size
Fire code requires metal duct, not flexible plastic
The duct material is incompatible with bathroom humidity levels

Correct answer: Moisture-laden air is being discharged into the attic, promoting mold and rot

Exhausting warm, moist bathroom air directly into the attic introduces significant moisture that can condense on structural members and sheathing, leading to mold, rot, and insulation damage.

Question 61: What is the purpose of a bonding jumper in an electrical system?

To protect against lightning strikes
To separate the neutral and ground conductors at sub-panels
To connect grounded metal parts to ensure a low-impedance fault path (Correct answer)
To increase the ampacity of the main service

Correct answer: To connect grounded metal parts to ensure a low-impedance fault path

A bonding jumper connects all metallic components of the electrical system to ensure a reliable path for fault current to flow back to the source.

Question 62: When a home inspector identifies reversed polarity at a receptacle, what does that mean?

The receptacle has too high a voltage for its rating
The receptacle is wired in a series rather than parallel circuit
The ground and neutral wires have been swapped
The hot and neutral wires are connected to the wrong terminals (Correct answer)

Correct answer: The hot and neutral wires are connected to the wrong terminals

Reversed polarity means the hot wire is connected to the neutral terminal and vice versa, which can make some appliances dangerous even when switched off.

Question 63: When inspecting a crawl space, a home inspector notices that several support posts rest directly on the soil without footings. What is the primary concern?

The posts may not meet height requirements
The posts may rot faster
Settlement and shifting of posts due to lack of proper load distribution to stable soil (Correct answer)
Moisture may enter through the soil

Correct answer: Settlement and shifting of posts due to lack of proper load distribution to stable soil

Without footings, posts can sink unevenly into soil as loads are not distributed over an adequate bearing area, leading to structural settlement and potential failure.

Question 64: According to the InterNACHI Standards of Practice for an exterior inspection, what is the generally recommended minimum slope for the ground surface within the first 10 feet of the foundation?

A rise of 2 inches towards the foundation to create a swale.
A fall of at least 1 inch for every 10 feet.
A slope that is perfectly level to allow for water absorption.
A fall of at least 6 inches. (Correct answer)

Correct answer: A fall of at least 6 inches.

The InterNACHI Standards of Practice and general building principles recommend that the ground should slope away from the foundation with a minimum fall of 6 inches within the first 10 feet. This positive grading is crucial for directing surface water away from the structure and preventing moisture intrusion into the basement, crawlspace, or foundation, which could lead to significant structural damage.

Question 65: Which type of retaining wall deficiency is considered a safety hazard during an exterior inspection?

Mortar joint discoloration
Efflorescence on block surface
Vegetation growing at wall base
Leaning or bulging wall with no weep holes (Correct answer)

Correct answer: Leaning or bulging wall with no weep holes

A leaning or bulging retaining wall without weep holes indicates hydrostatic pressure buildup that can cause catastrophic wall failure.

Question 66: What condition should a home inspector report when observing exposed nail heads on the surface of asphalt shingles?

A deficiency requiring repair as exposed nails are a potential leak source (Correct answer)
Evidence of a secondary layer of roofing applied over the first
An acceptable installation technique for steep slopes
Normal appearance of architectural shingles viewed at certain angles

Correct answer: A deficiency requiring repair as exposed nails are a potential leak source

Exposed nail heads on shingle surfaces indicate improper nailing above the nail zone and are a reportable deficiency as they create a direct pathway for water infiltration.

Question 67: According to common plumbing codes, a P-trap is installed at each fixture to block sewer gases from entering the home. What is the generally accepted minimum and maximum water seal depth for a standard P-trap?

1 inch minimum, 3 inches maximum
4 inches minimum, 6 inches maximum
2 inches minimum, 4 inches maximum (Correct answer)
0.5 inches minimum, 2 inches maximum

Correct answer: 2 inches minimum, 4 inches maximum

Most plumbing codes specify that a standard fixture P-trap must maintain a water seal of at least 2 inches to be effective against sewer gas and no more than 4 inches. A seal deeper than 4 inches can slow drainage and make it more likely to trap debris, while a seal less than 2 inches is more susceptible to evaporation or being siphoned out.

Question 68: An inspector notices that a bathroom exhaust fan vents into the attic instead of to the exterior. What is the concern?

It will cause elevated electric bills
It reduces combustion air to the furnace
Moisture and mold can accumulate in the attic (Correct answer)
The fan motor will overheat

Correct answer: Moisture and mold can accumulate in the attic

Exhausting humid bathroom air into an attic introduces moisture that can lead to condensation, wood rot, and mold growth on framing and sheathing.

Question 69: What is the maximum temperature the water heater thermostat should be set to in order to prevent scalding while also inhibiting Legionella bacteria growth?

140°F
110°F
100°F
120°F (Correct answer)

Correct answer: 120°F

120°F is the commonly recommended setting that balances scald prevention with inhibiting Legionella growth, per most health and safety guidelines.

Question 70: An InterNACHI home inspector notices that the roof sheathing panels have visible gaps between them with no H-clips installed. What is the structural significance?

The gaps indicate the sheathing is the wrong thickness for the rafter spacing
Missing H-clips only affect the fire rating of the roof assembly
The gaps will allow attic ventilation, which is actually beneficial
Without edge support, unsupported sheathing edges can deflect under load causing waves in the roof surface (Correct answer)

Correct answer: Without edge support, unsupported sheathing edges can deflect under load causing waves in the roof surface

H-clips provide edge support between rafters preventing unsupported sheathing edges from deflecting under load, which can cause visible waviness and eventual panel failure.

Question 71: During an HVAC inspection, what does a home inspector typically verify about the condensate drain system?

Refrigerant pressure at the drain valve
That the drain line discharges to the sanitary sewer only
Drain pipe diameter matches the compressor BTU rating
That the primary drain is clear and a secondary drain or overflow switch is present (Correct answer)

Correct answer: That the primary drain is clear and a secondary drain or overflow switch is present

Inspectors verify the primary drain is unobstructed and that a secondary overflow drain or float switch exists to prevent water damage if the primary drain clogs.

Question 72: A home inspector observes ice dams on the eaves of a house after a winter storm. Which attic condition most likely contributed to their formation?

Ridge vents allowing warm exterior air into the attic during thaws
Excessive attic ventilation causing rapid heat loss
Heat escaping through inadequate or missing attic insulation warming the roof deck (Correct answer)
Roof shingles with high solar absorptance retaining daytime heat

Correct answer: Heat escaping through inadequate or missing attic insulation warming the roof deck

Heat escaping from the living space through insufficient attic insulation warms the roof deck, melting snow that refreezes at the cold eaves and forms ice dams.

Question 73: What condition does an inspector suspect when they find the area around a toilet base is soft, stained, or the flooring feels spongy?

Excessive toilet flush pressure
A failed wax ring seal causing chronic leakage (Correct answer)
An undersized supply line
Condensation from a cold tank

Correct answer: A failed wax ring seal causing chronic leakage

A failed wax ring allows sewage and water to leak at the base of the toilet with each flush, leading to floor rot, mold, and structural damage over time.

Question 74: Which of the following best describes proper head flashing installation above an exterior door or window?

Flashing sits on top of the casing trim only
Flashing is caulked to the face of the wall above the opening
Flashing is installed behind the siding and extends over the top of the door or window casing to shed water outward (Correct answer)
Flashing is only required on north-facing elevations

Correct answer: Flashing is installed behind the siding and extends over the top of the door or window casing to shed water outward

Head flashing must be integrated behind the cladding and project over the casing so water is directed outward and away from the opening.

Question 75: A home inspector notices the bottom course of lap siding is within 2 inches of grade. What is the primary concern?

Increased risk of wood rot and pest entry (Correct answer)
Inadequate ventilation behind siding
Violation of setback requirements
Aesthetic appearance

Correct answer: Increased risk of wood rot and pest entry

Siding that is too close to grade is exposed to soil moisture and splash-back, accelerating rot and providing a pathway for termites.

Question 76: What is the purpose of a chase cover on a factory-built or prefabricated chimney?

To cap and weatherproof the framed chimney chase surrounding the metal flue pipe (Correct answer)
To provide a spark arrestor at the chimney top
To support the weight of the chimney cap above the flue termination
To increase the flue draft by narrowing the exhaust outlet

Correct answer: To cap and weatherproof the framed chimney chase surrounding the metal flue pipe

A chase cover is a flat or sloped metal panel that caps the top of a wood-framed chimney chase, protecting the interior framing from rain and moisture infiltration.

Question 77: According to InterNACHI standards, what is an inspector's responsibility when they cannot access an electrical panel due to stored items blocking it?

Skip the panel and note no deficiencies were observed
Report the panel as inaccessible and recommend evaluation (Correct answer)
Move the items and inspect the panel
Assume the panel is code-compliant if the home passed prior inspections

Correct answer: Report the panel as inaccessible and recommend evaluation

When a panel cannot be accessed, the inspector must report it as inaccessible and recommend that it be evaluated when access is available.

Question 78: What minimum wire gauge is required for a 20-amp branch circuit using copper conductors?

8 AWG
12 AWG (Correct answer)
14 AWG
10 AWG

Correct answer: 12 AWG

12 AWG copper wire is rated for 20-amp circuits; using 14 AWG on a 20-amp breaker is undersized and a fire hazard.

Question 79: An inspector finds that the gap between a wood deck and the house exterior wall is filled with caulk instead of flashing. What is the concern?

Caulk creates an airtight seal that traps heat
The gap size violates building code
Caulk is a fire hazard near the house
Caulk will eventually fail and allow water intrusion behind the siding (Correct answer)

Correct answer: Caulk will eventually fail and allow water intrusion behind the siding

Caulk is a maintenance item that deteriorates over time; proper flashing provides a durable, physical barrier to water at the deck-to-house junction.

Question 80: Which condition observed at a wood fence is most likely to indicate structural failure is imminent?

Fence boards with gaps between them
Fence posts that are rotted at or below grade level (Correct answer)
Surface weathering and graying of fence boards
Paint peeling from fence rails

Correct answer: Fence posts that are rotted at or below grade level

Rotted posts at grade level lose structural integrity and can no longer support the fence, making failure and collapse likely.

Question 81: What should a home inspector check regarding electrical systems?

Check the aesthetic design of outlets.
Only check if lights work.
Check the age of electrical appliances.
Check for outdated or unsafe wiring (Correct answer)

Correct answer: Check for outdated or unsafe wiring

When inspecting electrical systems, a home inspector's primary concern is safety and functionality. This involves checking for hazards such as outdated wiring (e.g., knob and tube, aluminum), improper grounding, overloaded circuits, and damaged components, all of which can pose significant fire or shock risks. The aesthetic design of outlets or the age of electrical appliances are not the main focus.

Question 82: What safety precaution should be taken when inspecting electrical systems?

Using insulated tools and safety equipment (Correct answer)
Turning off all electrical power before inspection.
Inspecting live electrical panels without protection.
Inspecting without gloves.

Correct answer: Using insulated tools and safety equipment

Inspecting electrical systems, especially live panels, carries inherent risks of electrical shock and injury. Therefore, it is crucial for inspectors to use appropriate personal protective equipment (PPE) such as insulated gloves and safety glasses, and to utilize insulated tools. These precautions minimize the risk of accidental contact with live components and ensure the inspector's safety.

Question 83: A home inspector observes that a split-system AC compressor is located in a utility closet inside the home. What is the most significant concern?

The refrigerant lines will be too short
Noise transmission to living areas
Limited access for future service
The condenser coil cannot reject heat properly indoors, making the system ineffective (Correct answer)

Correct answer: The condenser coil cannot reject heat properly indoors, making the system ineffective

Air-cooled condensing units must be outdoors to reject heat to the atmosphere; placing one indoors prevents proper heat rejection and will cause the system to fail.

Question 84: What is an HVAC system responsible for?

Lighting and electrical systems.
Heating, cooling, and air quality management (Correct answer)
Plumbing systems.
Building insulation.

Correct answer: Heating, cooling, and air quality management

HVAC stands for Heating, Ventilation, and Air Conditioning, encompassing the systems that control a building's indoor climate. Its primary responsibility is to maintain comfortable temperatures through heating and cooling, while also managing air quality by filtering and circulating fresh air. This comprehensive approach ensures occupant comfort, health, and energy efficiency.

Question 85: What does the presence of stair-step cracking in brick veneer most commonly indicate?

Differential settlement of the foundation (Correct answer)
Overloading of the brick wall
Normal thermal expansion
Improper mortar mix ratio

Correct answer: Differential settlement of the foundation

Stair-step cracks follow mortar joints and typically indicate differential foundation settlement, which can be a significant structural concern.

Question 86: What is the significance of finding displaced or missing mortar (tuckpointing failure) in a chimney's brick joints?

Water can penetrate the joints, freeze, expand, and accelerate masonry deterioration (Correct answer)
Flue liner replacement is required immediately
The chimney cap is oversized
The chimney's height does not meet code

Correct answer: Water can penetrate the joints, freeze, expand, and accelerate masonry deterioration

Open mortar joints allow water infiltration; freeze-thaw cycles cause spalling and can eventually compromise chimney structural integrity.

Question 87: An inspector observes a roof with two layers of asphalt shingles and significant wear on the top layer. What is the correct finding?

Both layers must be counted together to determine remaining service life
Two-layer roofs are prohibited and the lower layer must be immediately removed
The roof has reached the maximum allowable layers in most jurisdictions and requires a full tear-off before re-roofing (Correct answer)
A third layer may be added per local code before a full tear-off is required

Correct answer: The roof has reached the maximum allowable layers in most jurisdictions and requires a full tear-off before re-roofing

Most building codes allow a maximum of two layers of asphalt shingles; adding a third layer typically requires a complete tear-off of existing material first.

Question 88: An inspector finds a gas furnace with a cracked heat exchanger. What is the recommended course of action?

Increase combustion air supply to compensate
Note it for future monitoring
Recommend immediate discontinuation of use and professional repair (Correct answer)
Seal the crack with furnace cement before re-inspection

Correct answer: Recommend immediate discontinuation of use and professional repair

A cracked heat exchanger can allow carbon monoxide to mix with supply air and enter living spaces, making it a life-safety issue requiring immediate action.

Question 89: Which pipe material is identified by its distinctive orange color and is used for gas supply lines?

CSST
HDPE
Corrugated stainless steel tubing with orange jacket (CSST) (Correct answer)
CPVC

Correct answer: Corrugated stainless steel tubing with orange jacket (CSST)

CSST (corrugated stainless steel tubing) with an orange jacket is a flexible gas piping product; it must be properly bonded to mitigate lightning strike risks.

Question 90: What is the required arc-fault circuit interrupter (AFCI) protection for bedroom circuits in homes built to current NEC standards?

AFCI protection is optional in bedrooms
AFCI protection is required only in homes over 2,000 square feet
AFCI protection is required for all 120V, 15- and 20-amp branch circuits in bedrooms (Correct answer)
AFCI protection is required only for circuits with more than four outlets

Correct answer: AFCI protection is required for all 120V, 15- and 20-amp branch circuits in bedrooms

The NEC requires AFCI protection for all 120V, 15- and 20-amp branch circuits in bedrooms to reduce fire risk from arc faults in cords and wiring.

Question 91: Which roof covering material has the longest typical service life under normal conditions?

3-tab asphalt shingles
Wood shakes
Slate (Correct answer)
Architectural asphalt shingles

Correct answer: Slate

Natural slate roofing can last 75–150 years or more, significantly outlasting other common residential roofing materials.

Question 92: What does the term 'double-tapping' refer to in electrical panel inspections?

Using two ground wires on one breaker
Wiring a circuit with two hot wires only
Connecting two conductors to a single breaker terminal (Correct answer)
Installing two panels in series

Correct answer: Connecting two conductors to a single breaker terminal

Double-tapping occurs when two wires are connected to a single breaker terminal, which is a defect unless the breaker is rated for it.

Question 93: Which of the following is a sign of a failing supply stop valve under a sink?

Low hot water pressure only
The faucet aerator is clogged
The drain empties slowly
Mineral deposits or corrosion around the valve packing nut (Correct answer)

Correct answer: Mineral deposits or corrosion around the valve packing nut

Mineral deposits or corrosion around the packing nut of a stop valve indicate a slow leak or deteriorating stem seal that can worsen over time.

Question 94: Which roof component prevents water from entering at the intersection of a roof plane and a vertical wall?

Drip edge
Valley flashing
Ridge cap
Step flashing (Correct answer)

Correct answer: Step flashing

Step flashing consists of L-shaped metal pieces installed in courses along with the shingles where a roof meets a vertical wall.

Question 95: When inspecting wood siding, which condition most strongly suggests active moisture intrusion?

Faded paint color
Cupping or buckling of boards (Correct answer)
Minor surface checking
Knot stains bleeding through paint

Correct answer: Cupping or buckling of boards

Cupping or buckling of wood siding indicates moisture has penetrated, causing the wood fibers to swell unevenly.

Question 96: What does an open ground condition mean at a three-prong receptacle?

The receptacle has too many devices plugged in
The ground wire is missing or not connected (Correct answer)
The hot wire is reversed with the neutral
The neutral wire is disconnected

Correct answer: The ground wire is missing or not connected

An open ground means the equipment grounding conductor is absent or disconnected, leaving no path for fault current.

Question 97: What is the primary safety purpose of bonding the metallic gas piping system to the electrical system's grounding electrode system?

To use the gas pipe as a primary grounding electrode for the electrical system.
To ensure that any electrical fault energizes the gas meter, causing it to shut off the gas flow.
To allow low-voltage appliance control signals to travel through the home's piping.
To create an equipotential plane, preventing a voltage difference between the gas pipe and other grounded objects during a fault or lightning strike. (Correct answer)

Correct answer: To create an equipotential plane, preventing a voltage difference between the gas pipe and other grounded objects during a fault or lightning strike.

Bonding connects all metallic systems (gas pipes, water pipes, etc.) to the electrical ground to keep them at the same electrical potential. In the event of a lightning strike or an electrical fault that energizes the piping, this connection prevents a dangerous voltage difference from developing between the pipe and another grounded appliance, which could cause an arc and potential fire or explosion. The gas pipe must be bonded, but it is prohibited from being used as the grounding electrode itself.

Question 98: What refrigerant has been used as the primary replacement for R-22 in residential air conditioning systems since 2010?

R-32
R-134a
R-407C
R-410A (Correct answer)

Correct answer: R-410A

R-410A became the dominant replacement refrigerant for R-22 in residential systems due to its higher efficiency and zero ozone depletion potential.

Question 99: A home inspector identifies a horizontal framing member in the upper third of the attic space, connecting opposing rafters near the ridge. What is the primary function of this component?

To provide a mounting surface for attic lighting fixtures.
To resist outward thrust of the rafters at the top plate level.
To prevent rafter separation from wind uplift forces at the ridge. (Correct answer)
To support the weight of the roof sheathing and covering.

Correct answer: To prevent rafter separation from wind uplift forces at the ridge.

This component is a collar tie (or ridge strap). Its primary function is to connect opposing rafters in the upper third of the attic space to resist wind uplift forces that could pull the rafters apart at the ridge. Rafter ties, located in the lower third, are responsible for resisting the outward thrust of the rafters at the wall's top plate.

Question 100: What is the recommended nailing pattern for asphalt shingles to prevent wind uplift?

4 nails per shingle placed in the nail zone above the adhesive strip (Correct answer)
Nails placed through the tab cutouts for visual alignment
2 nails per shingle at each end only
6 nails per shingle placed randomly across the shingle face

Correct answer: 4 nails per shingle placed in the nail zone above the adhesive strip

Standard practice requires 4 nails per shingle placed in the manufacturer's designated nail zone just above the adhesive strip for optimal wind resistance.

Question 101: Which material is commonly used in structural beams?

Fiberglass.
Wood, steel, or concrete (Correct answer)
Plastic.
Aluminum.

Correct answer: Wood, steel, or concrete

Structural beams are designed to carry loads and transfer them to columns or walls, providing essential support to the building. The choice of material depends on the building's design, load requirements, and span, with wood, steel, and concrete being the most common and effective materials due to their inherent strength, durability, and versatility in construction.

Question 102: During an interior inspection, you are evaluating a flight of stairs. You measure the height of each riser and find that the tallest riser is 7 1/2 inches and the shortest is 7 inches. According to modern building standards, what should you report?

The riser heights are acceptable as they are all under the 7 3/4-inch maximum.
The stairs are non-compliant because the minimum riser height is 7 1/4 inches.
The variation is only a concern if the tread depth is less than 11 inches.
The 1/2-inch variation between the tallest and shortest riser is a safety hazard. (Correct answer)

Correct answer: The 1/2-inch variation between the tallest and shortest riser is a safety hazard.

Building codes, such as the IRC, specify that the greatest riser height within any flight of stairs shall not exceed the smallest by more than 3/8 inch (0.375 inches). In this case, the variation is 1/2 inch (0.5 inches), which exceeds the allowable tolerance and creates an inconsistent stepping pattern, posing a trip hazard.

Question 103: Which of the following is an exclusion from the InterNACHI standard home inspection?

Visible attic structural components
Underground utilities and components (Correct answer)
Readily accessible HVAC air supply registers
Visible plumbing supply and drain pipes

Correct answer: Underground utilities and components

Underground utilities and components are specifically excluded from the InterNACHI standard inspection because they are not visible or accessible.

Question 104: An inspector finds that a stairway handrail is loose and wobbles significantly when tested. Under InterNACHI standards, this is classified as:

Acceptable if the rail has been in place for more than 10 years
A safety hazard requiring repair (Correct answer)
Only a concern if the stairway has more than 10 risers
A minor deficiency to monitor over time

Correct answer: A safety hazard requiring repair

A loose or unstable handrail is a safety hazard that must be reported regardless of the stair length, as it cannot provide adequate support if someone falls.

Question 105: When inspecting supply ducts in an unconditioned attic, an inspector should be most concerned about:

Rectangular versus round duct shape
Missing or inadequate insulation on ducts (Correct answer)
Duct color fading from UV exposure
Number of duct branches per trunk line

Correct answer: Missing or inadequate insulation on ducts

Uninsulated ducts in a hot attic lose significant conditioned air energy and can cause condensation, reducing system efficiency and potentially causing moisture damage.

Question 106: What is the correct installation sequence for drip edge at the rake (gable) edge of a roof?

Drip edge installed under the underlayment
Drip edge installed over the underlayment (Correct answer)
Drip edge installed with no underlayment required at rakes
Drip edge is not required at rake edges

Correct answer: Drip edge installed over the underlayment

At rake edges, drip edge is installed over the underlayment so water is directed away from the fascia and off the roof edge correctly.

Question 107: What is the primary concern with a sump pump that discharges into the sanitary sewer system?

The sump pump motor may overheat
It causes the sump pit to fill too quickly
It introduces groundwater into the sewage system, which is prohibited in most jurisdictions (Correct answer)
The discharge pipe diameter is usually too small

Correct answer: It introduces groundwater into the sewage system, which is prohibited in most jurisdictions

Discharging groundwater (clear water) into the sanitary sewer is prohibited in most areas because it overloads the sewage treatment system.

Question 108: What is the most common material used to line a masonry chimney flue in residential construction?

Poured-in-place refractory
Stainless steel flex liner
Cast-iron segmented liner
Clay tile (terracotta) (Correct answer)

Correct answer: Clay tile (terracotta)

Clay tile flue liners are the most commonly installed liner type in masonry chimneys because they are durable, heat-resistant, and cost-effective.

Question 109: A roof inspector finds that counter flashing at a chimney is embedded in the mortar joints but is not sealed. What is the correct assessment?

Counter flashing embedded in mortar joints is the correct installation method and does not require additional sealant (Correct answer)
This is a serious defect requiring immediate chimney demolition
Counter flashing must always be surface-mounted and sealed with caulk
The flashing is incorrectly installed and must be face-nailed to the chimney

Correct answer: Counter flashing embedded in mortar joints is the correct installation method and does not require additional sealant

Counter flashing correctly embedded (tuck-pointed) into chimney mortar joints provides a secure, water-resistant seal without relying on caulk alone.

Question 110: According to InterNACHI standards, when inspecting a home with multiple HVAC systems, what is required?

HVAC systems installed within the last 5 years are exempt from inspection
Each system must be tested for at least 30 minutes of continuous operation
Only the primary HVAC system serving the main living area needs to be inspected
All permanently installed heating and cooling systems must be inspected (Correct answer)

Correct answer: All permanently installed heating and cooling systems must be inspected

All permanently installed heating and cooling systems are within the scope of inspection and must be evaluated.

Question 111: A home inspector finds knob-and-tube wiring in an attic that has been covered with insulation. Why is this a concern?

Rodents are attracted to insulation near older wiring
Covering knob-and-tube wiring automatically voids the homeowner's insurance
Knob-and-tube wiring requires ventilation to dissipate heat, and insulation prevents this (Correct answer)
Insulation causes the wire insulation to degrade chemically

Correct answer: Knob-and-tube wiring requires ventilation to dissipate heat, and insulation prevents this

Knob-and-tube wiring relies on open air for heat dissipation, and burying it in insulation can cause dangerous overheating.

Question 112: A home inspector observes that floor joists run parallel to one side of a bathtub but the subfloor feels soft and spongy near the tub. What is the most likely structural cause?

The bathtub is too heavy for the floor system
Water damage from tub or plumbing leaks has caused decay in joists and subfloor (Correct answer)
The joists are spaced too far apart
The subfloor is the wrong thickness

Correct answer: Water damage from tub or plumbing leaks has caused decay in joists and subfloor

Soft, spongy subfloor near a bathtub most commonly indicates chronic water intrusion from the tub or plumbing has caused wood decay in the subfloor and underlying joists.

Question 113: When inspecting a garage, an inspector finds an outlet within 6 feet of a vehicle door that is not GFCI-protected. What is the correct assessment?

Only outlets near water sources require GFCI in a garage
A deficiency, as all garage outlets require GFCI protection regardless of location (Correct answer)
Acceptable if the garage was built before 1978
Acceptable if the outlet is on a 20-amp circuit

Correct answer: A deficiency, as all garage outlets require GFCI protection regardless of location

All receptacles in garages (except dedicated appliance circuits) require GFCI protection per NEC requirements, regardless of their location within the garage.

Question 114: What is the minimum distance a plumbing vent must extend above a flat roof where the roof is used as a deck or occupied space?

24 inches
12 inches
7 feet (Correct answer)
6 inches

Correct answer: 7 feet

When a roof is used as a deck or occupied area, vents must extend at least 7 feet above the roof surface to keep sewer gases away from occupants.

Question 115: Which of the following is NOT a required component of the InterNACHI inspection report?

Photographs of every inspected component (Correct answer)
The inspector's name and signature
Identification of deficiencies found
A description of the systems and components inspected

Correct answer: Photographs of every inspected component

InterNACHI standards do not require photographs of every inspected component, though photographs of deficiencies are recommended best practice.

Question 116: In a cold climate like North Dakota, where should the vapor retarder (e.g., kraft paper facing on insulation) be placed in an exterior wall assembly?

It is not required in very cold climates.
On the exterior side of the insulation, directly behind the sheathing.
On the interior side of the insulation, directly behind the drywall. (Correct answer)
In the middle of the wall cavity, between two layers of insulation.

Correct answer: On the interior side of the insulation, directly behind the drywall.

In cold climates, the goal is to prevent warm, moist air from the home's interior from migrating into the wall cavity where it could condense on cold surfaces. Therefore, the vapor retarder should be installed on the 'warm-in-winter' side, which is the interior side of the insulation, just behind the finished wall surface (drywall).

Question 117: An inspector observes a plumbing vent pipe that terminates inside an attic rather than through the roof. This is:

A defect that allows sewer gases to accumulate in the attic (Correct answer)
Only a concern if the attic is conditioned space
Permitted by code if the vent is 12 inches above the insulation
Acceptable if the attic is well-ventilated

Correct answer: A defect that allows sewer gases to accumulate in the attic

Plumbing vents must terminate to the exterior, typically through the roof; terminating inside an attic allows toxic and flammable sewer gases to accumulate.

Question 118: Which of the following components are part of a plumbing system?

Electrical panels.
Light fixtures.
Air conditioning units.
Pipes, faucets, and drainage systems (Correct answer)

Correct answer: Pipes, faucets, and drainage systems

A plumbing system is an intricate network designed to manage water flow within a building. Its core components include pipes, which transport water throughout the structure; faucets, which control the delivery of water at specific points; and drainage systems, which are responsible for collecting and removing wastewater. These elements work together to ensure efficient water distribution and waste removal.

Question 119: What does the Annual Fuel Utilization Efficiency (AFUE) rating of a furnace represent?

The effectiveness of the furnace's air filtration system.
The cooling efficiency of the system when paired with an air conditioner.
The percentage of fuel consumed that is converted into usable heat for the home over a year. (Correct answer)
The speed at which the furnace can heat a space, measured in BTUs per hour.

Correct answer: The percentage of fuel consumed that is converted into usable heat for the home over a year.

AFUE stands for Annual Fuel Utilization Efficiency and is a standardized measure of how efficiently a furnace converts its fuel source (like gas or oil) into heat over an entire heating season. An AFUE of 95% means that 95 cents of every dollar spent on fuel is converted to heat, while the other 5 cents are lost, typically through the flue.

Question 120: According to NEC, GFCI protection is required in which of the following locations?

Living room receptacles
Interior hallways
Bathroom receptacles (Correct answer)
Bedrooms

Correct answer: Bathroom receptacles

NEC mandates GFCI protection for all bathroom receptacles due to the proximity of water sources.

InterNACHI Certified Home Inspector Exam

The InterNACHI exam assesses a candidate's knowledge of home inspection standards, practices, and components, ensuring they can perform thorough and accurate inspections.

120

Questions

120 min

Time Limit

80%

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