InterNACHI Certified Home Inspector Exam — Questions and Answers

Question 1: What is the primary concern with a sump pump that discharges into the sanitary sewer system?

The discharge pipe diameter is usually too small
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)

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 2: Which of the following is an inspector REQUIRED to inspect according to the InterNACHI Exterior Standards of Practice?

The operation of storm windows and shutters.
Recreational facilities, such as playground equipment.
Fences and outbuildings.
Retaining walls that may adversely affect the structure. (Correct answer)

Correct answer: Retaining walls that may adversely affect the structure.

The InterNACHI Standards of Practice explicitly state that the inspector shall inspect retaining walls where they may adversely affect the structure due to moisture intrusion or potential failure. Items like fences, outbuildings, recreational equipment, and the operation of shutters are specifically listed as not required to be inspected.

Question 3: What is the InterNACHI-recommended minimum clearance between wood framing or siding and the soil grade?

12 inches
4 inches
2 inches
6 inches (Correct answer)

Correct answer: 6 inches

InterNACHI standards recommend at least 6 inches of clearance between wood elements and soil to reduce rot and termite risk.

Question 4: During a crawlspace inspection, you observe a floor joist that has a 3-inch diameter hole drilled through its center. The joist is a standard 2x8 dimensional lumber piece (actual dimension is 7.25 inches). According to building standards, what should be your primary concern?

The hole is located too close to a load-bearing wall.
Multiple holes are spaced too closely together.
The hole should have been square, not circular.
The hole's diameter exceeds the maximum allowable size. (Correct answer)

Correct answer: The hole's diameter exceeds the maximum allowable size.

According to building standards, the maximum diameter of a hole bored in a dimensional lumber joist should not exceed one-third of the joist's actual depth. For a 2x8 joist (7.25 inches deep), the maximum allowable hole size is approximately 2.42 inches (7.25 / 3). A 3-inch hole exceeds this limit and can compromise the structural integrity of the joist.

Question 5: What is the purpose of inspecting HVAC systems?

To decorate the ducts.
To ensure safety and efficiency (Correct answer)
To ensure a constant energy consumption.
To determine indoor air quality.

Correct answer: To ensure safety and efficiency

Inspecting HVAC systems is vital for two main reasons: safety and efficiency. Safety checks identify potential hazards such as carbon monoxide leaks from furnaces or electrical issues, preventing serious risks. Efficiency checks ensure the system operates optimally, reducing energy consumption and utility costs, while also maintaining comfortable indoor air quality.

Question 6: Which roof covering material has the longest typical service life under normal conditions?

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

Correct answer: Slate

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

Question 7: Which condition is most likely to cause 'wind washing' in an attic insulation system?

Ridge vent installed without baffles
Blown insulation that is too dense to allow air movement
Inadequate soffit vent area compared to ridge vent area (Correct answer)
Insufficient insulation depth at the attic floor center

Correct answer: Inadequate soffit vent area compared to ridge vent area

When ridge vent area exceeds soffit vent area, negative pressure can draw outside air under the insulation at the eaves, degrading its R-value through wind washing.

Question 8: An inspector finds that the garage door does not auto-reverse when a 2x4 board is placed flat on the floor in its path. What standard does this fail?

UL 325 auto-reverse requirement — door must reverse on contact with a 1.5-inch obstruction (Correct answer)
NFPA 13 sprinkler clearance rule
ADA accessible path requirement
IRC minimum door height requirement

Correct answer: UL 325 auto-reverse requirement — door must reverse on contact with a 1.5-inch obstruction

UL 325 requires automatic garage door openers to reverse when the door contacts an object no higher than 1.5 inches (the height of a 2x4 laid flat).

Question 9: Which insulation material has the highest risk of moisture absorption and subsequent loss of R-value when exposed to water intrusion?

Rigid extruded polystyrene (XPS)
Open-cell spray foam (Correct answer)
Fiberglass batts
Closed-cell spray foam

Correct answer: Open-cell spray foam

Open-cell spray foam is highly permeable and will absorb water, losing its R-value and potentially harboring mold if exposed to moisture intrusion.

Question 10: 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
Interior of the chimney flue (Correct answer)
Gutters and downspouts
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.

Question 11: What refrigerant has been used as the primary replacement for R-22 in residential air conditioning systems since 2010?

R-32
R-407C
R-134a
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 12: What is the purpose of a cricket (saddle) installed behind a chimney?

To improve attic ventilation near the chimney
To divert water around the chimney and prevent ponding (Correct answer)
To seal the chimney cap against wind-driven rain
To provide additional structural support to the chimney

Correct answer: To divert water around the chimney and prevent ponding

A cricket is a peaked saddle structure built behind wide chimneys to redirect water away and prevent it from pooling against the chimney base.

Question 13: While inspecting a concrete driveway, you notice several sections have settled, creating uneven surfaces and significant cracks wider than 1/2 inch. One section has heaved upwards, creating a pronounced trip hazard at the entrance to the garage. Which of the following is the most appropriate action?

Note the cracks but classify them as minor cosmetic issues.
Recommend immediate replacement of the entire driveway.
Advise the client that driveways are outside the scope of a home inspection.
Report the settled sections and the significant trip hazard as material defects in need of correction. (Correct answer)

Correct answer: Report the settled sections and the significant trip hazard as material defects in need of correction.

The InterNACHI Standards of Practice require the inspection of adjacent walkways and driveways. Significant cracks and settlement, especially those creating a trip hazard, are considered material defects that affect safety and functionality. These conditions should be clearly reported as in need of correction or further evaluation by a qualified contractor.

Question 14: 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 15: While inspecting a central air conditioning system on a warm day, an inspector observes a significant amount of ice on the evaporator coil and the suction line. Which of the following is the most likely cause of this condition?

The outdoor condenser unit is dirty and cannot reject heat effectively.
The system is oversized for the home.
Restricted airflow across the evaporator coil or a low refrigerant charge. (Correct answer)
The thermostat is set to a very low temperature.

Correct answer: Restricted airflow across the evaporator coil or a low refrigerant charge.

Ice formation on the evaporator coil and suction line during cooling mode is a classic symptom of the coil becoming too cold (dropping below 32°F). This is typically caused by either insufficient warm air moving across the coil to be absorbed or a low refrigerant level, which causes a pressure drop and excessive cooling. A dirty filter is a common cause of restricted airflow.

Question 16: What is the term for the phenomenon where warm interior air leaks into a wall or ceiling cavity and deposits moisture as it cools near the exterior surface?

Interstitial condensation by diffusion
Dew point deposition
Vapor diffusion
Air transport condensation (Correct answer)

Correct answer: Air transport condensation

Air transport condensation occurs when air-transported moisture — not diffusion — carries water vapor into a cavity where it condenses on cooler surfaces, often causing far more damage than vapor diffusion.

Question 17: What does the term 'exposure' refer to when describing asphalt shingles?

The granule color rating under UV exposure
The number of shingle layers over the deck
The portion of the shingle visible after installation (Correct answer)
The total length of the shingle from top to bottom

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 18: What is a 'bootleg ground' (also called a false ground) in a receptacle?

An improper ground installed in a two-wire circuit using EMT conduit
A ground rod driven outside the foundation without bonding
A jumper wire connecting the neutral terminal to the ground terminal (Correct answer)
A ground wire run externally along the baseboard

Correct answer: A jumper wire connecting the neutral terminal to the ground terminal

A bootleg ground uses a jumper between the neutral and ground slots, making a tester show 'correct' but providing no real shock protection.

Question 19: Which component in a heat pump system reverses the refrigerant flow to switch between heating and cooling modes?

Expansion valve
Reversing valve (four-way valve) (Correct answer)
Accumulator
Compressor

Correct answer: Reversing valve (four-way valve)

The reversing valve (four-way valve) redirects refrigerant flow so the heat pump can absorb heat from outside in winter or reject heat outside in summer.

Question 20: When inspecting a roof, an inspector finds granules accumulating in the gutters. What does this most likely indicate?

The shingles are approaching end of useful life (Correct answer)
Normal weathering on a new roof
Improper attic ventilation
Ice dam formation

Correct answer: The shingles are approaching end of useful life

Significant granule loss in gutters typically indicates shingles are aging and losing their protective coating, signaling they are near the end of their service life.

Question 21: A home inspector finds Federal Pacific Electric (FPE) Stab-Lok panel in a home. What should the report state?

FPE Stab-Lok panels have documented reliability concerns and evaluation by a licensed electrician is recommended (Correct answer)
FPE panels are recalled and must be replaced immediately
No action needed if the panel is less than 30 years old
FPE panels are acceptable if breakers do not trip during inspection

Correct answer: FPE Stab-Lok panels have documented reliability concerns and evaluation by a licensed electrician is recommended

FPE Stab-Lok panels have a documented history of breaker failures and fire risk; inspectors should recommend evaluation but cannot require replacement.

Question 22: Which of the following is a common cause of chimney backdrafting?

An oversized flue relative to the fireplace opening
Negative pressure inside the home created by exhaust fans (Correct answer)
An improperly sized chimney cap restricting the flue outlet
Creosote buildup on the damper plate

Correct answer: Negative pressure inside the home created by exhaust fans

When exhaust fans (kitchen, bath, whole-house) depressurize a tightly sealed home, outside air can be drawn down the chimney flue to equalize pressure, causing backdrafting.

Question 23: What does 'water hammer' refer to in a plumbing system?

Low water pressure at fixtures
Corrosion buildup inside steel pipes
A banging noise caused by sudden water flow stoppage (Correct answer)
Excessive mineral deposits in a water heater

Correct answer: A banging noise caused by sudden water flow stoppage

Water hammer is a pressure surge or banging noise that occurs when flowing water is abruptly stopped, often by fast-closing valves.

Question 24: A home inspector finds a 15-amp breaker protecting a circuit with 12 AWG wire. This is:

Not permitted under any code
Acceptable — the wire exceeds the breaker's ampacity rating (Correct answer)
A concern only if the circuit serves a bathroom
A safety violation requiring immediate correction

Correct answer: Acceptable — the wire exceeds the breaker's ampacity rating

Using 12 AWG wire on a 15-amp breaker is acceptable because the wire can handle more current than the breaker will allow.

Question 25: When inspecting older homes, what type of wiring is characterized by two conductors insulated and wrapped together in a cloth-like jacket without a ground wire?

Non-metallic sheathed cable (NM)
Aluminum branch circuit wiring
Knob-and-tube wiring (Correct answer)
Conduit wiring

Correct answer: Knob-and-tube wiring

Knob-and-tube wiring uses separate hot and neutral conductors supported by ceramic knobs and tubes, with no equipment ground.

Question 26: What is the primary function of drip edge flashing installed along the eaves?

To create an air gap for ventilation under shingles
To prevent ice from lifting the first shingle course
To anchor the first course of shingles
To direct water off the roof edge into the gutter and away from the fascia (Correct answer)

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 27: When inspecting a gravity (non-forced air) warm-air furnace, what is the primary concern an inspector should note?

Absence of a programmable thermostat
Low AFUE efficiency rating
Age and condition of the heat exchanger, which is difficult to inspect and often deteriorated (Correct answer)
Lack of electronic ignition

Correct answer: Age and condition of the heat exchanger, which is difficult to inspect and often deteriorated

Gravity furnaces are typically very old, and their large cast-iron heat exchangers are prone to cracking, creating a serious carbon monoxide hazard that warrants specialist evaluation.

Question 28: During an inspection, the inspector finds that a steel I-beam in the basement has significant rust scaling and section loss. The MOST important evaluation is:

Whether the rust has stained the concrete floor below the beam
The color and texture of the rust, which indicates the type of steel used
Whether the section loss has reduced the beam's load-carrying capacity (Correct answer)
The age of the beam based on the rust pattern

Correct answer: Whether the section loss has reduced the beam's load-carrying capacity

Rust scaling that causes section loss directly reduces the structural capacity of the steel beam and requires engineer evaluation to determine if replacement or reinforcement is needed.

Question 29: What is the significance of finding open-ground three-prong outlets in a home built in 1965?

Open-ground outlets are only a concern in kitchens and bathrooms
This indicates aluminum wiring is present
This was code-compliant at the time and requires no action
The outlets were retrofitted with three-prong outlets without adding a ground conductor (Correct answer)

Correct answer: The outlets were retrofitted with three-prong outlets without adding a ground conductor

Open-ground outlets indicate three-prong outlets were installed without a proper equipment ground, which removes shock protection for appliances.

Question 30: What is the required arc-fault circuit interrupter (AFCI) protection for bedroom circuits in homes built to current NEC standards?

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

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 31: What is the minimum burial depth for UF (underground feeder) cable supplying a residential outdoor circuit?

24 inches
12 inches (Correct answer)
18 inches
6 inches

Correct answer: 12 inches

NEC requires UF cable to be buried a minimum of 12 inches deep for residential branch circuits, though RMC conduit allows shallower burial.

Question 32: 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 33: A home inspector notices the condensate drain line on an air handler is dripping water at the connection joint. What should be reported?

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

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 34: An inspector opens a main service panel and observes two white neutral conductors terminated under a single screw on the neutral bus bar. Which of the following is the most accurate description of this defect?

Reversed polarity
A bonded neutral bus
Over-fused circuit
Double-tapped neutrals (Correct answer)

Correct answer: Double-tapped neutrals

This condition is commonly called "double-tapped neutrals." Most panelboard lugs are designed for only one conductor. Terminating two wires under one screw can lead to a loose connection over time due to expansion and contraction, which can cause overheating, arcing, and a potential fire hazard.

Question 35: 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 cricket or saddle (Correct answer)
An extra layer of underlayment
A dedicated gutter system
A secondary headwall flashing

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 36: 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?

12 inches
7 feet (Correct answer)
24 inches
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 37: An inspector observes stair-step cracking in a brick veneer wall near a window corner. This pattern most likely indicates:

Differential foundation settlement (Correct answer)
Normal curing shrinkage of new brick
Improper mortar mix during construction
Thermal expansion of the brick

Correct answer: Differential foundation settlement

Stair-step cracks following mortar joints near openings are a classic sign of differential foundation settlement causing racking forces in the masonry.

Question 38: According to the National Electrical Code (NEC), what is the minimum required clear working space in front of a residential electrical panel?

24 inches deep and 24 inches wide
30 inches deep and 36 inches wide
36 inches deep and 30 inches wide (Correct answer)
48 inches deep and 48 inches wide

Correct answer: 36 inches deep and 30 inches wide

The NEC Section 110.26 requires a clear working space of at least 36 inches of depth in front of the panel, 30 inches of width (or the width of the equipment, whichever is greater), and a height of 6.5 feet. This space allows a service person to work safely and provides an escape path in an emergency.

Question 39: When inspecting a metal roof, an inspector notices white, powdery deposits near fasteners. What does this indicate?

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

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 40: Which of the following represents the MOST significant life-safety hazard associated with a cracked heat exchanger in a gas-fired furnace?

The furnace may overheat and shut down on a safety limit switch.
A significant decrease in the furnace's heating efficiency.
The potential for combustion gases, like carbon monoxide, to mix with the circulated household air. (Correct answer)
Loud banging or popping noises during furnace operation.

Correct answer: The potential for combustion gases, like carbon monoxide, to mix with the circulated household air.

The primary and most critical danger of a cracked heat exchanger is the breach in separation between the combustion chamber and the breathable air supply. This can allow toxic flue gases, most notably carbon monoxide (CO), to enter the ductwork and be distributed throughout the home, creating a life-threatening situation.

Question 41: What is the purpose of an air admittance valve (AAV) in a drain system?

To add air pressure to increase drain flow
To release excess pressure from drain lines
To allow air into the drain to prevent siphoning of trap seals without venting through the roof (Correct answer)
To filter odors from plumbing vents

Correct answer: To allow air into the drain to prevent siphoning of trap seals without venting through the roof

An AAV is a one-way valve that opens to admit air when negative pressure develops in the drain, preventing trap siphoning without a conventional vent pipe.

Question 42: What is the role of a plumber in home inspections?

To fix HVAC systems.
To install new electrical systems.
To provide electrical inspections.
To check plumbing systems for leaks and blockages (Correct answer)

Correct answer: To check plumbing systems for leaks and blockages

During a home inspection, a plumber's specialized role is to thoroughly examine the property's entire plumbing system. This includes meticulously checking for any signs of leaks, identifying potential blockages in drains or pipes, and assessing the overall condition and functionality of water supply and waste removal components. Their expertise ensures that the plumbing infrastructure is sound and free from immediate or potential issues.

Question 43: What is the recommended maximum temperature rise across a gas furnace heat exchanger?

10–20°F
80–100°F
25–35°F
35–70°F (Correct answer)

Correct answer: 35–70°F

Most gas furnaces are designed for a temperature rise of 35–70°F across the heat exchanger; values outside this range indicate airflow or equipment issues.

Question 44: Which wire color in a standard 120V residential circuit is the grounded conductor?

Red
Green
White (Correct answer)
Black

Correct answer: White

The white wire is the grounded (neutral) conductor in a standard 120V residential circuit.

Question 45: Which type of ventilation system uses negative pressure created by exhaust fans to draw fresh air through intentional or unintentional openings in the building envelope?

Energy recovery ventilation
Supply-only ventilation
Balanced ventilation
Exhaust-only ventilation (Correct answer)

Correct answer: Exhaust-only ventilation

Exhaust-only systems depressurize the building, drawing outdoor air in through leaks and intentional inlets to replace the exhausted air.

Question 46: What is the minimum clearance typically required around an outdoor condensing unit for proper airflow?

12–18 inches on all sides with 4–5 feet above (Correct answer)
36 inches on all sides with 10 feet above
6 inches on all sides
24 inches on all sides with 8 feet above

Correct answer: 12–18 inches on all sides with 4–5 feet above

Most manufacturers require at least 12–18 inches of clearance on the sides and 4–5 feet of unobstructed space above the condenser for adequate airflow.

Question 47: What amperage rating is typically required for a dedicated 240V circuit serving a modern electric clothes dryer?

30 amps (Correct answer)
20 amps
50 amps
15 amps

Correct answer: 30 amps

Electric clothes dryers require a dedicated 30-amp, 240V circuit with a 4-wire connection per current NEC standards.

Question 48: According to the International Residential Code (IRC), which of the following situations requires the installation of safety glazing?

An upper sash of a double-hung window in a second-floor bedroom.
Glazing in a swinging door that separates a bedroom from a hallway. (Correct answer)
A fixed window in a living room where the bottom edge is 24 inches above the floor and the total area is 8 square feet.
A glass panel in a cabinet door located in a kitchen.

Correct answer: Glazing in a swinging door that separates a bedroom from a hallway.

The IRC identifies specific hazardous locations where safety glazing is required to prevent injury from broken glass. Glazing in all swinging doors is considered a hazardous location and requires safety glass, such as tempered or laminated glass. The other scenarios do not meet the specific criteria for a hazardous location requiring safety glazing.

Question 49: What is the primary function of a condensate trap on the drain line of an indoor air handler coil?

To provide a convenient location for adding cleaning tablets to the system.
To create a water seal that prevents air from being drawn into or blown out of the unit through the drain. (Correct answer)
To prevent insects and pests from entering the unit through the drain line.
To measure the amount of water being removed from the air.

Correct answer: To create a water seal that prevents air from being drawn into or blown out of the unit through the drain.

A condensate trap holds a small amount of water to create a seal. In an air handler where the coil is under negative pressure (before the blower), this seal prevents unconditioned air from being sucked into the unit through the drain line. In a furnace where the coil is under positive pressure (after the blower), it prevents conditioned air from being blown out. This ensures proper drainage and maintains system efficiency.

Question 50: Which pipe material is identified by its distinctive orange color and is used for gas supply lines?

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

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 51: A home inspector observes that the water heater's temperature and pressure relief valve discharge pipe terminates into a bucket. This is:

Required by code in some states
Acceptable if the valve is tested annually
Acceptable if the bucket is plastic
A deficiency requiring correction (Correct answer)

Correct answer: A deficiency requiring correction

The TPR valve discharge pipe must terminate within 6 inches of the floor, into a drain, or to the exterior — never into a bucket or container.

Question 52: 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 53: 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 slope that is perfectly level to allow for water absorption.
A fall of at least 1 inch for every 10 feet.
A fall of at least 6 inches. (Correct answer)
A rise of 2 inches towards the foundation to create a swale.

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 54: When inspecting exterior stairs, what baluster spacing deficiency is a safety hazard?

Balusters painted a dark color
Baluster spacing greater than 4 inches, allowing a child's head to pass through (Correct answer)
Balusters made of wood rather than metal
Balusters installed at a slight angle

Correct answer: Baluster spacing greater than 4 inches, allowing a child's head to pass through

Baluster spacing exceeding 4 inches creates a strangulation or entrapment hazard for young children whose heads can pass through the opening.

Question 55: What is a common sign of structural damage?

Visible cracks or misaligned doors (Correct answer)
Properly functioning HVAC.
No visible damage.
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 56: What is the function of the smoke shelf inside a masonry fireplace?

To provide a mounting surface for the throat damper assembly
To separate the primary combustion air from the secondary air supply
To increase the velocity of smoke entering the flue
To catch falling debris and prevent downdrafts from pushing smoke into the room (Correct answer)

Correct answer: To catch falling debris and prevent downdrafts from pushing smoke into the room

The smoke shelf is a horizontal ledge located behind the damper that catches debris falling from the flue and disrupts downdrafts, preventing smoke from entering the living space.

Question 57: An inspector, while evaluating a home's drain, waste, and vent (DWV) system, hears a distinct gurgling sound from the bathtub drain immediately after flushing a nearby toilet. Both fixtures appear to drain adequately otherwise. What is the most probable cause of this gurgling sound?

The P-trap for the bathtub has lost its seal due to evaporation.
Excessive water pressure in the supply lines.
A partial blockage or inadequate plumbing vent. (Correct answer)
A cracked toilet bowl.

Correct answer: A partial blockage or inadequate plumbing vent.

Gurgling sounds from adjacent fixtures are a classic sign of a venting problem. When the toilet is flushed, a large volume of water rushing down the drain creates negative pressure. If the vent stack is blocked or improperly installed, the system will draw air from the easiest source, which is often through the P-trap of a nearby fixture like a bathtub, causing the water in the trap to gurgle.

Question 58: Which roof component prevents water from entering at the intersection of a roof plane and a vertical wall?

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

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 59: In a residential electrical system, what is the purpose of an anti-oxidant compound applied to aluminum wiring connections?

To increase electrical conductivity above copper
To bond aluminum to copper at splices
To prevent oxidation that increases resistance at connections (Correct answer)
To color-code aluminum wire terminations

Correct answer: To prevent oxidation that increases resistance at connections

Anti-oxidant compound prevents the formation of aluminum oxide at connections, which increases resistance and creates heat buildup.

Question 60: What is the typical minimum clearance required between a gas furnace and combustible materials?

Per manufacturer specifications (Correct answer)
12 inches
1 inch
6 inches

Correct answer: Per manufacturer specifications

Clearance requirements vary by furnace model and must follow the manufacturer's installation instructions, which take precedence over generic rules.

Question 61: Why is grounding important in electrical systems?

To improve the energy efficiency of electrical appliances.
To improve lighting.
To increase the electrical load.
To protect against electrical shock and fire hazards (Correct answer)

Correct answer: To protect against electrical shock and fire hazards

Grounding provides a safe path for electricity to flow directly into the earth in the event of a fault or surge, rather than through a person or the appliance itself. This critical safety feature helps prevent electrical shocks, reduces the risk of electrical fires by safely dissipating excess current, and protects sensitive electronic equipment from damage. It is a fundamental component of a safe electrical system.

Question 62: What does the presence of stair-step cracking in brick veneer most commonly indicate?

Normal thermal expansion
Differential settlement of the foundation (Correct answer)
Overloading of the brick wall
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 63: What is the concern when a home inspector finds multiple extension cords being used as permanent wiring in a bedroom?

Extension cords used as permanent wiring are a fire and shock hazard and indicate insufficient outlets (Correct answer)
Extension cords used indoors pose no safety risk
Extension cords are only a concern in kitchens and bathrooms
Extension cords are acceptable as permanent wiring if they are heavy-duty rated

Correct answer: Extension cords used as permanent wiring are a fire and shock hazard and indicate insufficient outlets

Extension cords are not designed for permanent use, can overheat, and their use indicates a need for additional permanently wired outlets.

Question 64: Which of the following is a common defect found with older two-prong (ungrounded) receptacles?

They lack a neutral conductor
They have no equipment grounding conductor, offering no protection against faults (Correct answer)
They are rated for less amperage than modern receptacles
They are only rated for 110 volts

Correct answer: They have no equipment grounding conductor, offering no protection against faults

Two-prong receptacles lack the grounding conductor, meaning there is no path to safely divert fault current away from users or equipment.

Question 65: 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?

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

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 66: What does AFUE measure in heating equipment?

Annual fuel utilization efficiency (Correct answer)
Air flow uniformity efficiency
Average furnace utility expenditure
Airside fan unit efficiency

Correct answer: Annual fuel utilization efficiency

AFUE (Annual Fuel Utilization Efficiency) expresses as a percentage how much of the fuel's energy is converted to usable heat over a heating season.

Question 67: 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
Insulation causes the wire insulation to degrade chemically
Knob-and-tube wiring requires ventilation to dissipate heat, and insulation prevents this (Correct answer)

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 68: What condition does 'blistering' on an asphalt shingle roof indicate?

Over-driven fasteners causing buckling
Algae growth beneath the granule surface
Trapped moisture or volatile compounds escaping from the shingle (Correct answer)
Hail damage from a recent storm

Correct answer: Trapped moisture or volatile compounds escaping from the shingle

Blistering results from trapped moisture or volatile compounds in the asphalt that vaporize and create raised bubbles on the shingle surface.

Question 69: When inspecting wood siding, which condition most strongly suggests active moisture intrusion?

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

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 70: Which roofing material requires the installation of a solid or spaced wood deck for proper performance?

Wood shingles and shakes (Correct answer)
EPDM membrane
Modified bitumen
Built-up roofing (BUR)

Correct answer: Wood shingles and shakes

Wood shingles and shakes require either solid or spaced sheathing to allow airflow beneath them for drying and to prevent moisture-related decay.

Question 71: During a home inspection, the inspector notices the main water shutoff valve is a gate valve that is difficult to turn. The inspector should:

Force it fully closed to test it
Note it as a deficiency and recommend evaluation by a plumber (Correct answer)
Ignore it since gate valves are rarely used
Replace it on the spot with a ball valve

Correct answer: Note it as a deficiency and recommend evaluation by a plumber

A difficult-to-operate main shutoff is a safety concern and should be noted; the inspector should not force it, as it may break.

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
Heat escaping through inadequate or missing attic insulation warming the roof deck (Correct answer)
Excessive attic ventilation causing rapid heat loss
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: While inspecting a recently built home, you observe that the solid hardwood flooring on the main level is 'cupping,' with the edges of the boards being slightly higher than their centers. What is the most likely cause of this condition?

The subfloor is uneven, causing the boards to deflect under load.
There is a moisture imbalance, with the bottom of the flooring having a higher moisture content than the top. (Correct answer)
The home's interior is excessively dry due to the heating system.
The flooring was installed with an insufficient expansion gap at the perimeter walls.

Correct answer: There is a moisture imbalance, with the bottom of the flooring having a higher moisture content than the top.

Hardwood floor cupping occurs when there is a moisture imbalance through the thickness of the wood. The bottom of the board absorbs more moisture than the top surface, causing it to expand and push the edges upward. This is often due to moisture from a subfloor, crawlspace, or basement. Excessive dryness typically causes gapping, not cupping.

Question 74: 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 insulated glass unit (IGU) (Correct answer)
The window frame
The interior weatherstripping

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 75: Why is it important to hire a certified home inspector?

To provide a general opinion.
To provide a detailed valuation of the property.
To ensure an accurate, professional assessment (Correct answer)
To save money.

Correct answer: To ensure an accurate, professional assessment

Hiring a certified home inspector ensures that the assessment of a property's condition is conducted by a knowledgeable professional adhering to industry standards. Certification signifies specialized training and expertise, allowing the inspector to accurately identify and report on potential issues. This provides clients with an unbiased, thorough, and reliable evaluation, protecting their interests during a real estate transaction.

Question 76: Why is it important to inspect plumbing and HVAC systems?

To add decorative elements.
To ensure systems are functioning efficiently and safely (Correct answer)
To improve building aesthetics.
To increase energy consumption.

Correct answer: To ensure systems are functioning efficiently and safely

Regular inspections of plumbing and HVAC systems are crucial for maintaining a healthy and safe living environment. These inspections identify potential issues like leaks, blockages, or inefficient operation, which can lead to costly repairs, water damage, or poor indoor air quality. Ensuring these systems function correctly prevents hazards, prolongs their lifespan, and optimizes energy consumption.

Question 77: 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
Whole-house fans
Ridge and soffit vents (Correct answer)
Solar-powered attic fans

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 78: What is the minimum recommended R-value for attic insulation in most U.S. climate zones according to energy standards?

R-30
R-49
R-38 (Correct answer)
R-19

Correct answer: R-38

R-38 is commonly the minimum recommended R-value for attic insulation in most U.S. climate zones, though colder zones may require R-49 or higher.

Question 79: Which exterior lighting condition is a reportable deficiency during a home inspection?

Timer-controlled porch light
Incandescent bulbs instead of LED
Light fixture located above a garage door
Missing covers on exterior electrical boxes exposing live wiring (Correct answer)

Correct answer: Missing covers on exterior electrical boxes exposing live wiring

Exterior electrical boxes must have weatherproof covers; missing covers expose energized wiring to the elements and create shock and fire hazards.

Question 80: 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?

24 hours
48 hours (Correct answer)
12 hours
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 81: Which of the following is NOT part of the structural system of a building?

Columns
Electrical wiring (Correct answer)
Foundations
Beams

Correct answer: Electrical wiring

The structural system includes components that provide the physical support and framework of the building, such as foundations, beams, columns, and load-bearing walls. Electrical wiring, while essential for the home's function, is part of the electrical system and does not contribute to the building's structural integrity or support its weight.

Question 82: According to InterNACHI standards, what is an inspector's responsibility when they cannot access an electrical panel due to stored items blocking it?

Report the panel as inaccessible and recommend evaluation (Correct answer)
Move the items and inspect the panel
Skip the panel and note no deficiencies were observed
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 83: In a modern home, which of the following locations requires receptacles to have BOTH arc-fault (AFCI) and ground-fault (GFCI) protection?

Hallways and closets
Attached garages
Bedrooms
Kitchens and laundry areas (Correct answer)

Correct answer: Kitchens and laundry areas

The National Electrical Code requires AFCI protection for 15- and 20-amp branch circuits in most living areas of a dwelling, including kitchens and laundry rooms, to protect against fire hazards from arcing. It also requires GFCI protection for receptacles in locations with a high risk of shock, such as those near water in kitchens and laundry areas. Therefore, these locations require both forms of protection.

Question 84: What defect is indicated when a wood floor shows cupping — edges higher than the center of each board?

Excessive foot traffic has compressed the center of each board
The floor finish has caused the wood to swell from the top surface
Moisture is present on the underside of the flooring, causing the bottom to expand more than the top (Correct answer)
The floor was installed during low humidity and has since expanded

Correct answer: Moisture is present on the underside of the flooring, causing the bottom to expand more than the top

Cupping in hardwood flooring is caused by higher moisture content on the bottom of the boards than the top, causing the bottom to expand and the edges to lift.

Question 85: What does an open ground condition mean at a three-prong receptacle?

The ground wire is missing or not connected (Correct answer)
The hot wire is reversed with the neutral
The receptacle has too many devices plugged in
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 86: According to the InterNACHI Standards of Practice for a residential inspection, which action is an inspector required to perform when evaluating the foundation and structural components?

Provide an engineering analysis of the adequacy of the foundation.
Move stored items in the crawlspace to access all foundation walls.
Report on observed indications of possible foundation movement. (Correct answer)
Determine the size, spacing, and adequacy of foundation anchor bolts.

Correct answer: Report on observed indications of possible foundation movement.

The InterNACHI Standards of Practice require an inspector to report on observed indications of possible foundation movement. This includes signs like sheetrock cracks, brick cracks, out-of-square door frames, and unlevel floors. The standards explicitly state that inspectors are not required to provide engineering services, move stored items, or determine the adequacy of foundation bolting or other structural systems.

Question 87: 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
Galvanized steel
Copper type M

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 88: What does it mean when a home inspector reports 'evidence of prior repair' at a plumbing pipe?

The repair was permitted and should be trusted
The pipe material was upgraded from an older type
The pipe has been recently replaced and is in excellent condition
There are visible signs of past leaks or patching that may indicate ongoing problems (Correct answer)

Correct answer: There are visible signs of past leaks or patching that may indicate ongoing problems

Evidence of prior repair (tape, epoxy, clamps, or staining around a patch) suggests the area has experienced past failure and warrants closer evaluation for recurring issues.

Question 89: What does InterNACHI's Standards of Practice require inspectors to do when they cannot visually inspect the interior of a flue?

Perform a smoke test using a smoke pellet to verify draft
Describe the limitation and recommend further evaluation by a qualified specialist (Correct answer)
Use a flashlight and mirror to verify partial liner condition only
Decline to report on the fireplace or flue condition at all

Correct answer: Describe the limitation and recommend further evaluation by a qualified specialist

When an inspector cannot fully inspect a component, InterNACHI's SOP requires disclosing the limitation in the report and recommending further evaluation by a qualified professional.

Question 90: 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 91: Which ceiling finish condition should a home inspector report as a safety concern requiring immediate evaluation?

Sagging or bulging ceiling sections (Correct answer)
Minor hairline cracks in drywall tape joints
Water stains that appear dry and old
Nail pops visible through paint

Correct answer: Sagging or bulging ceiling sections

Sagging or bulging ceiling sections indicate structural failure of the ceiling assembly and pose an immediate collapse hazard requiring prompt evaluation.

Question 92: What is the primary function of a structural system in a building?

To regulate indoor climate.
To enhance aesthetic appeal.
To provide plumbing services.
To support the building's weight and resist forces (Correct answer)

Correct answer: To support the building's weight and resist forces

The structural system of a building, comprising elements like foundations, walls, beams, and columns, is fundamentally designed to bear the entire weight of the structure. It also resists external forces such as wind, seismic activity, and snow loads, ensuring the building's stability, integrity, and safety. Without a sound structural system, the building would be unstable and unsafe.

Question 93: What is the hearth extension requirement for a fireplace with an opening greater than 6 square feet?

Extends at least 24 inches in all directions from the firebox opening
Extends at least 12 inches in front and 8 inches on each side
Extends at least 20 inches in front of and 12 inches beyond each side of the opening (Correct answer)
Extends at least 16 inches in front of and 8 inches beyond each side of the opening

Correct answer: Extends at least 20 inches in front of and 12 inches beyond each side of the opening

IRC requires that for fireplaces with openings greater than 6 square feet, the hearth extension must be at least 20 inches deep and extend at least 12 inches beyond each side of the opening.

Question 94: When inspecting the flashing at a chimney base, which condition represents a deficiency requiring reporting?

Aluminum step flashing installed on an asphalt shingle roof
Base flashing extending 4 inches up the chimney face
Caulk-only installation with no metal counter-flashing embedded in mortar (Correct answer)
Step flashing that overlaps the counter-flashing by 2 inches

Correct answer: Caulk-only installation with no metal counter-flashing embedded in mortar

Relying on caulk alone without embedded counter-flashing is a maintenance workaround that fails over time; proper installation requires metal counter-flashing set into the chimney mortar joints.

Question 95: Per InterNACHI inspection standards, what minimum clearance to combustible materials is required for a factory-built (zero-clearance) fireplace?

Minimum 2 inches to all combustible framing members
Must follow the clearances listed by the manufacturer's installation instructions (Correct answer)
No clearance required because the firebox is pre-insulated
Same as masonry fireplaces — 2 inches to all sides

Correct answer: Must follow the clearances listed by the manufacturer's installation instructions

Factory-built fireplaces are listed appliances, and inspectors must verify that clearances match the manufacturer's installation instructions, as these vary by model.

Question 96: What does the 'net free area' of a vent refer to?

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

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 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 create an equipotential plane, preventing a voltage difference between the gas pipe and other grounded objects during a fault or lightning strike. (Correct answer)
To allow low-voltage appliance control signals to travel through the home's piping.

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: During an attic inspection, you observe flexible ductwork that is compressed in several areas and has multiple sharp 90-degree bends. What is the primary defect to report?

The ductwork material is not approved for residential use.
The flexible ductwork should be replaced with rigid metal ducting.
The ductwork is not adequately insulated for an attic application.
The sharp bends and compression severely restrict airflow, reducing system performance and efficiency. (Correct answer)

Correct answer: The sharp bends and compression severely restrict airflow, reducing system performance and efficiency.

Flexible ductwork must be installed with gentle bends (radius greater than one duct diameter) and without compression to ensure proper airflow. Sharp bends and kinks create significant friction and turbulence, which chokes off the airflow, leading to poor heating/cooling performance, wasted energy, and strain on the HVAC equipment.

Question 99: What is the minimum clearance required between the top of a residential electrical panel and the ceiling?

3 feet
No minimum required
6 feet (Correct answer)
6.5 feet

Correct answer: 6 feet

NEC requires a minimum headroom clearance of 6 feet above electrical panels to allow safe working access.

Question 100: Which condition indicates a cracked heat exchanger in a gas furnace?

Yellow or orange burner flame (Correct answer)
High static pressure readings
Visible rust on the exterior cabinet
Soot accumulation on burner ports

Correct answer: Yellow or orange burner flame

A cracked heat exchanger allows combustion gases to mix with supply air, causing the burner flame to roll out or appear yellow/orange due to disrupted airflow.

Question 101: How does moisture affect structural components?

It makes the structure more flexible.
It causes deterioration and damage (Correct answer)
It improves the structural strength.
It has no effect.

Correct answer: It causes deterioration and damage

Moisture is a significant threat to structural components, especially those made of wood or concrete. It can lead to wood rot, mold growth, rust in steel components, and the weakening or spalling of concrete, all of which compromise the material's integrity and the overall structural stability of the building. Prolonged moisture exposure can severely shorten a structure's lifespan.

Question 102: An inspector discovers that the grounding electrode conductor at the main panel is a #6 AWG copper wire connected to a metal water pipe. What should be noted if the water pipe is plastic near the street?

The grounding system may be compromised if the metallic water pipe section is short and discontinuous (Correct answer)
Grounding to water pipes is no longer permitted under any circumstance
The grounding system is fully adequate as long as any metal pipe exists
Plastic pipe replacements have no effect on grounding systems

Correct answer: The grounding system may be compromised if the metallic water pipe section is short and discontinuous

If a plastic section interrupts the metal water pipe before reaching earth, the pipe segment cannot serve as a grounding electrode and the system is compromised.

Question 103: An inspector finds that a washing machine drain hose is inserted more than 4 inches into the standpipe. This creates a risk of:

Vibration damage to the standpipe
Back-siphonage of contaminated water into the machine (Correct answer)
Excessive noise during the drain cycle
Overloading the drain system

Correct answer: Back-siphonage of contaminated water into the machine

Inserting the drain hose too deep into the standpipe can create a siphon that draws contaminated drain water back into the washing machine.

Question 104: An inspector notices that the cleanout plug on a main drain cleanout is missing. The significance of this finding is:

Only significant if the home has a septic system
Sewer gases can enter the home and vermin can access the drain system (Correct answer)
No concern — cleanouts are optional access points
The drain system will not function without the plug

Correct answer: Sewer gases can enter the home and vermin can access the drain system

A missing cleanout plug allows sewer gases to escape into the structure and provides an entry point for insects and rodents into the drain system.

Question 105: What should a home inspector do if they find a serious issue during the inspection?

Ignore the issue.
Hide it from the report.
Report it and recommend further evaluation (Correct answer)
Fix the issue.

Correct answer: Report it and recommend further evaluation

A home inspector's role is to identify and report on the condition of the property, not to perform repairs or offer specific solutions. If a serious issue is discovered, the inspector must clearly document it in the inspection report and recommend that a qualified specialist, such as a structural engineer or licensed contractor, be consulted for further in-depth evaluation and repair recommendations.

Question 106: What is the maximum height at which a wall switch controlling a light may be installed per accessibility standards?

48 inches (Correct answer)
44 inches
36 inches
54 inches

Correct answer: 48 inches

ADA and accessibility guidelines recommend wall switches be installed no higher than 48 inches above the finished floor.

Question 107: What is a 'p-trap' designed to do?

Regulate water pressure at fixtures
Hold water to block sewer gases from entering the home (Correct answer)
Prevent backflow in the water supply
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 108: Why is it important to inspect electrical systems regularly?

To improve indoor lighting.
To reduce the building's electrical consumption.
To ensure energy efficiency.
To prevent safety hazards and ensure code compliance (Correct answer)

Correct answer: To prevent safety hazards and ensure code compliance

Regular inspection of electrical systems is essential to identify and address potential safety hazards, such as faulty wiring, outdated components, or overloaded circuits, before they lead to fires or electrical shocks. It also ensures the system remains compliant with current electrical codes, which are designed to protect occupants and property from electrical dangers. This proactive approach prevents serious incidents.

Question 109: 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 can accelerate membrane deterioration and indicates inadequate drainage (Correct answer)
Ponding only becomes a deficiency if it exceeds 2 inches in depth
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 110: What is the primary function of a plumbing system in a building?

To provide electrical power.
To regulate indoor temperature.
To insulate the building.
To distribute clean water and remove waste (Correct answer)

Correct answer: To distribute clean water and remove waste

The plumbing system is fundamental to a building's habitability and hygiene. Its primary function involves two critical aspects: delivering a safe and reliable supply of clean, potable water to various fixtures and appliances, and efficiently removing wastewater and sewage from the property. This dual role ensures sanitation, health, and convenience for occupants.

Question 111: When inspecting vinyl siding, which defect is most likely to allow bulk water entry?

Slight wave pattern in siding panels
Missing J-channel or unsealed penetrations at openings (Correct answer)
Siding installed with tight nailing (no expansion gap)
Color fading on south-facing walls

Correct answer: Missing J-channel or unsealed penetrations at openings

Missing J-channel or unsealed gaps around windows, doors, and penetrations leave openings where bulk water can enter behind the siding.

Question 112: An inspector sees that a downspout terminates at the foundation wall with no extension. What is the recommended correction?

Paint the downspout to prevent corrosion
Install a gutter guard on the associated gutter
Add a splash block or extension to direct water at least 6 feet from the foundation (Correct answer)
Replace the downspout with a larger diameter pipe

Correct answer: Add a splash block or extension to direct water at least 6 feet from the foundation

Downspouts should discharge water well away from the foundation to prevent soil saturation and basement water intrusion.

Question 113: What is the purpose of a weep screed at the base of stucco cladding?

To anchor the stucco to the framing
To allow moisture trapped behind stucco to drain out (Correct answer)
To prevent thermal expansion cracking
To provide a decorative trim line

Correct answer: To allow moisture trapped behind stucco to drain out

A weep screed is a metal flashing strip at the base of stucco that allows any water infiltrating behind the cladding to escape.

Question 114: A home inspector observes cupping of asphalt shingles. What is the most likely cause?

Moisture imbalance causing the shingle edges to curl upward (Correct answer)
Too many fasteners per shingle
Shingles installed in cold weather
Improper ventilation causing heat buildup

Correct answer: Moisture imbalance causing the shingle edges to curl upward

Cupping occurs when shingle edges turn upward due to moisture differential between the top and bottom surfaces of the shingle.

Question 115: An inspector observes that the grout between ceramic floor tiles in a kitchen is darker in some areas and lighter in others. What does this uneven coloration most likely indicate?

Different batches of grout were used during installation
The tiles were installed at different times
The floor receives uneven sunlight exposure
Moisture beneath the tile is wicking up through cracked grout joints (Correct answer)

Correct answer: Moisture beneath the tile is wicking up through cracked grout joints

Uneven or dark grout coloration often indicates moisture migrating up through compromised grout joints from beneath the tile, suggesting a moisture problem below the floor.

Question 116: Which is a sign that an electrical system is outdated?

Exposed wiring.
Too many outlets in one room.
Improper electrical meter placement.
Lack of grounding or outdated wiring (Correct answer)

Correct answer: Lack of grounding or outdated wiring

Signs of an outdated electrical system often include the absence of grounding in outlets, which is a critical safety feature, or the presence of older wiring types like knob and tube or aluminum wiring. These older systems may not meet modern safety standards, lack sufficient capacity for contemporary electrical demands, and can pose increased risks of fire or electrical shock.

Question 117: What exterior condition would prompt an inspector to recommend further evaluation by a licensed structural engineer?

Paint peeling from wood trim
Minor weathering of window caulk
Horizontal cracks in a concrete block foundation wall (Correct answer)
Hairline shrinkage cracks in stucco

Correct answer: Horizontal cracks in a concrete block foundation wall

Horizontal cracks in concrete block walls indicate lateral soil pressure is overcoming the wall's resistance, a potentially serious structural failure mode.

Question 118: 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 119: A chimney cap serves which of the following primary functions?

Meeting code requirements for spark arrestor clearance
Preventing rain, debris, and animals from entering the flue (Correct answer)
Reducing thermal expansion stress on the chimney crown
Increasing updraft velocity to improve combustion

Correct answer: Preventing rain, debris, and animals from entering the flue

A chimney cap covers the top of the flue opening to keep out rain, leaves, birds, and small animals while still allowing combustion gases to exit.

Question 120: Which type of pipe is NOT approved for use as a water supply line under current plumbing codes?

Polybutylene (Correct answer)
CPVC
Copper
PEX

Correct answer: Polybutylene

Polybutylene (PB) pipe was recalled and is no longer approved due to its tendency to fail and leak, especially at fittings.

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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