InterNACHI Certified Home Inspector Exam — Questions and Answers

Question 1: 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)
Permitted by code if the vent is 12 inches above the insulation
Only a concern if the attic is conditioned space
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 2: An inspector observes that a wood sill plate is soft and crumbles when probed with a screwdriver. What is the most likely cause and structural implication?

Wood decay from moisture has compromised the structural connection between foundation and framing (Correct answer)
The lumber was improperly kiln-dried before installation
Normal aging of older-growth lumber over several decades
The wood species is naturally soft and unsuitable for sill plates

Correct answer: Wood decay from moisture has compromised the structural connection between foundation and framing

A soft, crumbling sill plate indicates wood decay, which destroys the critical structural link that transfers all wall and roof loads to the foundation.

Question 3: What condition at a chimney cricket (saddle) should an inspector flag as a deficiency?

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

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

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

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 5: What should a home inspector check regarding electrical systems?

Check for outdated or unsafe wiring (Correct answer)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

Correct answer: Check for outdated or unsafe wiring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 6: During a home inspection, an inspector finds that the ridge board in the attic has a significant sag. The MOST likely structural cause is:

Snow load has permanently compressed the ridge board
The attic ventilation is insufficient
The ridge board is too wide for the span
Inadequate collar ties or rafter ties allowing the rafters to spread (Correct answer)

Correct answer: Inadequate collar ties or rafter ties allowing the rafters to spread

A sagging ridge board typically results from rafter spread caused by missing or inadequate collar ties, allowing the roof structure to push outward and down.

Question 7: 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?

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

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 8: A home inspector finds a Federal Pacific Stab-Lok electrical panel. What should the inspector note?

These panels have a documented history of breaker failure and fire risk (Correct answer)
It is only a concern if the home is over 50 years old
It requires immediate red-tag condemnation
It is a high-quality panel with enhanced safety features

Correct answer: These panels have a documented history of breaker failure and fire risk

Federal Pacific Stab-Lok panels have a well-documented history of failing to trip under overcurrent conditions, posing a fire hazard.

Question 9: Which type of insulation is most appropriate for sealing small irregular gaps around pipes and wiring penetrations through top plates?

Two-component spray polyurethane foam (Correct answer)
Fiberglass batt scraps
Rigid foam board cut to size
Blown-in cellulose

Correct answer: Two-component spray polyurethane foam

Two-component spray polyurethane foam expands to fill irregular shapes and adheres to most surfaces, making it ideal for air-sealing small penetrations.

Question 10: What is the minimum clearance required between the top of a residential electrical panel and the ceiling?

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

Correct answer: 6 feet

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

Question 11: What does the term 'exposure' refer to when describing asphalt shingles?

The number of shingle layers over the deck
The granule color rating under UV exposure
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 12: A home inspector observes that a cantilevered floor joist extending to support a bay window has developed a pronounced downward sag at its tip. This most likely indicates:

The exterior cladding on the bay window is pulling the structure downward
The bay window glass is too heavy for the framing design
Normal long-term creep of wood under sustained load is within acceptable limits
The cantilever length exceeds safe limits or the back-span anchorage is insufficient (Correct answer)

Correct answer: The cantilever length exceeds safe limits or the back-span anchorage is insufficient

Excessive cantilever length without adequate back-span anchorage allows the cantilevered joists to tip downward, often indicating a design or construction deficiency.

Question 13: What is the function of the smoke shelf inside a masonry fireplace?

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

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 14: What is the primary function of a plumbing system in a building?

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

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 15: While inspecting an attic, you observe a non-IC-rated recessed light fixture with blown-in insulation packed tightly against its housing. What is the PRIMARY safety hazard this condition presents?

A significant fire hazard due to overheating. (Correct answer)
Reduced light output from the bulb.
Degradation of the insulation's R-value.
A drafty condition causing energy loss.

Correct answer: A significant fire hazard due to overheating.

Non-IC (Insulation Contact) rated fixtures are not designed to be in direct contact with insulation. They require a clearance, typically 3 inches, to allow heat to dissipate. When insulation is packed against them, the fixture can overheat, creating a serious fire hazard. IC-rated fixtures are specifically designed to be safely covered with insulation.

Question 16: What is the primary function of drip edge flashing installed along the eaves?

To anchor the first course of shingles
To create an air gap for ventilation under shingles
To prevent ice from lifting the first shingle course
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 17: What does the presence of active corrosion (green staining) at copper pipe joints indicate?

The pipes were recently installed
The pipes are lead-free
Pinhole leaks or ongoing moisture at the joint (Correct answer)
High water hardness in the area

Correct answer: Pinhole leaks or ongoing moisture at the joint

Green staining (verdigris) at copper joints indicates active or past moisture, suggesting a slow leak or pinhole corrosion that warrants further evaluation.

Question 18: A home inspector observes double-tapped circuit breakers in a panel. What does this mean?

The panel uses a dual-bus design
The panel has twice the normal capacity
Two wires are connected to a single breaker terminal not rated for it (Correct answer)
A tandem breaker is properly installed

Correct answer: Two wires are connected to a single breaker terminal not rated for it

Double-tapping means two conductors are connected to a breaker terminal designed for only one, which is a safety defect unless the breaker is listed for two conductors.

Question 19: What is the maximum height at which a wall switch controlling a light may be installed per accessibility standards?

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

Correct answer: 48 inches

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

Question 20: An inspector notices that the cleanout plug on a main drain cleanout is missing. The significance of this finding is:

No concern — cleanouts are optional access points
Only significant if the home has a septic system
Sewer gases can enter the home and vermin can access the drain system (Correct answer)
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 21: Which type of heat pump extracts heat energy from groundwater or the earth rather than outdoor air?

Dual-fuel heat pump
Geothermal (ground-source) heat pump (Correct answer)
Ductless mini-split heat pump
Variable refrigerant flow (VRF) system

Correct answer: Geothermal (ground-source) heat pump

Geothermal (ground-source) heat pumps use the stable temperature of the ground or groundwater as a heat source in winter and a heat sink in summer.

Question 22: What does efflorescence on a masonry foundation wall indicate to a home inspector?

Mortar was over-troweled during construction
Water has moved through the masonry, depositing mineral salts on the surface (Correct answer)
The wall was painted with latex paint
The wall is in good condition and properly sealed

Correct answer: Water has moved through the masonry, depositing mineral salts on the surface

Efflorescence is the white mineral residue left when water migrates through masonry and evaporates, indicating moisture movement through the wall.

Question 23: A home inspector tests a window and finds it painted shut. How should this be reported?

It is only a concern in rooms designated as bedrooms
It is acceptable as it reduces air infiltration
It is a deficiency because windows must be operable for egress and ventilation (Correct answer)
It should be noted only if the window is in a room below grade

Correct answer: It is a deficiency because windows must be operable for egress and ventilation

Painted-shut windows are a deficiency because operable windows are required for emergency egress in sleeping rooms and for natural ventilation throughout the home.

Question 24: An inspector finds that a bathroom outlet is not GFCI-protected but is within 6 feet of a sink. What should be noted?

This is acceptable if the circuit is 15-amp
GFCI is only required within 3 feet of a sink
GFCI is optional in bathrooms built before 2000
This is a safety deficiency requiring correction (Correct answer)

Correct answer: This is a safety deficiency requiring correction

All bathroom outlets require GFCI protection regardless of distance from a water source, per current NEC requirements.

Question 25: Spalling observed on a masonry chimney exterior refers to:

Horizontal cracks forming along mortar joints between brick courses
White mineral deposits on the chimney surface
Flaking or breaking off of the face of brick or stone surfaces (Correct answer)
Separation of the chimney from the main structure at the foundation

Correct answer: Flaking or breaking off of the face of brick or stone surfaces

Spalling is the physical breaking, chipping, or flaking of masonry surfaces, typically caused by freeze-thaw cycles forcing absorbed moisture to expand inside the material.

Question 26: An inspector observes a service entrance cable with damaged outer insulation at the weatherhead. What is the primary concern?

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

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 27: An inspector observes diagonal cracks radiating from the corners of window and door openings in a concrete block wall. This pattern suggests:

Water infiltration deteriorating the mortar
Improper installation of window flashing
Thermal expansion cracking due to sun exposure
Settlement or movement causing stress concentrations at opening corners (Correct answer)

Correct answer: Settlement or movement causing stress concentrations at opening corners

Diagonal cracks radiating from corners of openings are classic indicators of differential settlement or structural movement creating stress concentrations at those points.

Question 28: What does it mean when an electrical panel has its neutral and ground buses bonded together in a sub-panel?

This indicates the sub-panel has an improper main breaker
This is a code-compliant practice in all panels
Bonding is only required in the main panel and permitted in sub-panels
This is a defect that creates a parallel neutral path and shock hazard (Correct answer)

Correct answer: This is a defect that creates a parallel neutral path and shock hazard

In sub-panels, the neutral and ground buses must be separated because bonding them creates a parallel return path that can energize ground wires.

Question 29: 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 acceptable as permanent wiring if they are heavy-duty rated
Extension cords are only a concern in kitchens and bathrooms

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 30: What is the primary safety purpose of the Temperature and Pressure Relief (TPR) valve installed on a residential water heater?

To prevent sediment from accumulating at the bottom of the tank.
To automatically regulate the daily operating temperature of the water.
To prevent dangerous pressure or temperature buildup by discharging water. (Correct answer)
To allow the homeowner to easily drain the tank for routine maintenance.

Correct answer: To prevent dangerous pressure or temperature buildup by discharging water.

The TPR valve is a critical safety device designed to open automatically if either the temperature (typically >210°F) or the pressure (typically >150 psi) inside the tank exceeds safe limits. By discharging water, it prevents a potentially catastrophic explosion.

Question 31: 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
0.5 inches minimum, 2 inches maximum
2 inches minimum, 4 inches maximum (Correct answer)
4 inches minimum, 6 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 32: What does a home inspector look for when evaluating whether blown-in cellulose insulation in an attic has settled significantly?

Presence of borate dust around the perimeter indicating movement
Color change from gray to brown indicating moisture damage
Depth ruler markings on attic trusses or joists indicating original fill depth (Correct answer)
Surface crust indicating the insulation dried out after settling

Correct answer: Depth ruler markings on attic trusses or joists indicating original fill depth

Depth rulers or markers installed at the time of insulation installation allow inspectors and homeowners to verify whether cellulose has settled below its original depth.

Question 33: During an inspection, you find that interior door hinges are binding and the door drags on the floor along one side. What condition does this most likely indicate?

Foundation settlement or structural movement (Correct answer)
Seasonal wood expansion
Improper door installation
Worn hinge hardware

Correct answer: Foundation settlement or structural movement

Doors that bind or drag on one side often indicate foundation settlement or structural movement that has racked the door frame out of square.

Question 34: What is the primary function of insulation baffles (rafter vents) installed in attic eave areas?

To increase the R-value of insulation near the eaves
To maintain a clear airway from soffit vents to the attic space above insulation (Correct answer)
To prevent rodents from entering through soffit vents
To redirect warm air from the living space toward the ridge

Correct answer: To maintain a clear airway from soffit vents to the attic space above insulation

Baffles create a channel that keeps soffit vent airflow clear of blown or batt insulation that might otherwise block the eave ventilation pathway.

Question 35: What does the term 'bearing capacity' refer to in the context of a home inspection structural evaluation?

The ability of the soil or structural member to support imposed loads without failure (Correct answer)
The resistance of a foundation to frost heave
The maximum load a structural member can carry before deflection
The weight of the building's structural frame itself

Correct answer: The ability of the soil or structural member to support imposed loads without failure

Bearing capacity is the maximum load per unit area that soil or a structural element can support without experiencing shear failure or excessive settlement.

Question 36: A home inspector finds that bathroom exhaust fans are ducted into the attic and terminate without an outlet. What deficiency does this represent?

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

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

To ensure systems are functioning efficiently and safely (Correct answer)
To add decorative elements.
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 38: What is the role of structural engineers in home inspections?

To manage the construction budget.
To install plumbing systems.
To install electrical wiring.
To inspect and design structural components (Correct answer)

Correct answer: To inspect and design structural components

While home inspectors identify potential structural issues, structural engineers are specialists who possess the expertise to perform in-depth analyses, diagnose complex structural problems, and design appropriate repair solutions. They are often called upon when a home inspector identifies significant structural concerns that require expert evaluation and precise engineering recommendations to ensure safety and stability.

Question 39: Which roof component prevents water from entering at the intersection of a roof plane and a vertical wall?

Ridge cap
Drip edge
Valley flashing
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 40: 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's diameter exceeds the maximum allowable size. (Correct answer)
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.

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 41: When inspecting a gas fireplace, which observation should an inspector report as a deficiency?

Ceramic fiber logs positioned per the manufacturer's diagram
A millivolt pilot light that remains on continuously
Yellow flames with black soot deposits on the firebox interior (Correct answer)
A glass front panel that becomes warm during operation

Correct answer: Yellow flames with black soot deposits on the firebox interior

Yellow flames and soot deposits in a gas appliance indicate incomplete combustion, which can signal improper air-to-gas ratio, burner obstruction, or CO production.

Question 42: Why is a home inspection report important for buyers and sellers?

It determines the value of the home.
It is used for tax purposes.
It helps buyers and sellers make informed decisions (Correct answer)
It is a mandatory legal document.

Correct answer: It helps buyers and sellers make informed decisions

The home inspection report provides an objective assessment of the property's condition, highlighting potential issues or necessary repairs. For buyers, this information is vital for negotiating price or repair requests, while sellers can use it to address issues proactively or disclose them. This transparency empowers both parties to make well-informed decisions, facilitating a smoother and more equitable real estate transaction.

Question 43: When inspecting a fireplace firebox, which condition would an InterNACHI inspector flag as a safety deficiency?

Ash pit door located below the firebox floor level
Cracks in the refractory firebrick panels exceeding 1/8 inch (Correct answer)
Presence of a glass-door screen assembly
Soot staining on the back wall above the damper shelf

Correct answer: Cracks in the refractory firebrick panels exceeding 1/8 inch

Cracks larger than 1/8 inch in firebrick panels can allow combustion gases and heat to escape into the surrounding structure, creating a fire hazard.

Question 44: What is a common plumbing issue in homes?

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

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 45: Which type of roof deck material is most susceptible to delamination when exposed to prolonged moisture?

Solid lumber boards
OSB (oriented strand board) (Correct answer)
Steel decking
Plywood

Correct answer: OSB (oriented strand board)

OSB is more susceptible to delamination and swelling from moisture exposure than plywood or solid lumber due to its composite wood fiber construction.

Question 46: A home inspector finds knob-and-tube wiring in an attic that has been covered with insulation. Why is this a concern?

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

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

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

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 48: Which is a sign that an electrical system is outdated?

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

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 49: 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)
Normal aging of plastic outlet covers
Indication of reversed polarity only
Overloaded neutral conductor

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 50: How many circuits are permitted to share a single neutral conductor in a multi-wire branch circuit (MWBC)?

Two circuits sharing one neutral on different hot legs (Correct answer)
Three circuits sharing one neutral on the same hot leg
Unlimited circuits if the neutral is oversized
One circuit per neutral

Correct answer: Two circuits sharing one neutral on different hot legs

An MWBC allows two 120V circuits on opposite hot legs to share one neutral, as the neutral currents cancel each other out under load.

Question 51: InterNACHI inspectors should report aluminum branch circuit wiring (post-1972) because it poses what risk?

It is not permitted in any residential application
Connections can loosen over time causing overheating and fire (Correct answer)
It corrodes faster than copper in wet environments
It has lower ampacity than copper of the same gauge

Correct answer: Connections can loosen over time causing overheating and fire

Aluminum wiring connections can oxidize and loosen, increasing resistance and creating a fire hazard at termination points.

Question 52: Which observation at a wood deck most directly indicates inadequate structural support?

Deck boards are spaced 1/4 inch apart
Handrail balusters are spaced 4 inches apart
Decking is installed perpendicular to joists
Posts are notched more than one-third of their depth for beam bearing (Correct answer)

Correct answer: Posts are notched more than one-third of their depth for beam bearing

Notching posts more than one-third of their depth significantly reduces load capacity and can lead to post splitting or failure.

Question 53: What is the purpose of a bonding jumper in an electrical system?

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

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 54: Which material is commonly used in structural beams?

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

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

Surface weathering and graying of fence boards
Fence posts that are rotted at or below grade level (Correct answer)
Fence boards with gaps between them
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 56: What is the minimum headlap required for standard 3-tab asphalt shingles?

6 inches
1 inch
4 inches
2 inches (Correct answer)

Correct answer: 2 inches

Standard 3-tab asphalt shingles require a minimum headlap of 2 inches to provide adequate weather protection at the overlapping joint.

Question 57: What is the role of a plumber in home inspections?

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

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

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

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 59: What is an HVAC system responsible for?

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

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 60: Which of the following attic ventilation systems relies on wind and natural convection (the principle that hot air rises) to function, without mechanical assistance?

Whole-house fans
Powered attic ventilators
Solar-powered attic fans
Ridge and soffit vents (Correct answer)

Correct answer: Ridge and soffit vents

Ridge and soffit vents are components of a passive ventilation system. Soffit vents act as intakes for cooler, lower air, while ridge vents serve as exhausts for hotter air that rises to the peak of the attic, creating continuous airflow without any mechanical parts.

Question 61: What does negative grading around a foundation indicate to a home inspector?

Soil slopes toward the foundation, risking water intrusion (Correct answer)
Soil slopes away from the foundation properly
Underground drainage is functioning correctly
The lot has been recently regraded

Correct answer: Soil slopes toward the foundation, risking water intrusion

Negative grading means the ground slopes toward the foundation, which can direct surface water into the basement or crawlspace.

Question 62: 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)
Aesthetic appearance
Violation of setback requirements
Inadequate ventilation behind siding

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 63: Which duct condition most significantly reduces HVAC system efficiency and should be documented during inspection?

Supply registers mounted in the floor
Round metal ducts with screwed connections
Uninsulated ducts in unconditioned attic space (Correct answer)
Flexible duct with minor bends

Correct answer: Uninsulated ducts in unconditioned attic space

Uninsulated ducts in an unconditioned attic can lose 25–40% of conditioned air energy to the surrounding environment, significantly degrading system efficiency.

Question 64: What does an open ground condition mean at a three-prong receptacle?

The ground wire is missing or not connected (Correct answer)
The receptacle has too many devices plugged in
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 65: When inspecting the guardrails on a porch that is 48 inches above the adjacent ground, you find that the balusters (spindles) are spaced 7 inches apart. What should be reported?

The baluster spacing is a safety hazard and should be reported as in need of correction. (Correct answer)
The guardrail height is the only required measurement.
The material of the balusters is more important than the spacing.
The spacing is acceptable for porches of this height.

Correct answer: The baluster spacing is a safety hazard and should be reported as in need of correction.

A common safety standard, and a specific item InterNACHI inspectors must report on, is improper spacing between balusters. Generally, balusters should be spaced so that a 4-inch sphere cannot pass through, to prevent small children from falling through. A 7-inch spacing is a significant safety hazard that must be reported as a defect in need of correction.

Question 66: 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
HDPE
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 67: What is the importance of a building's foundation?

It is primarily for decoration.
It is mainly for aesthetic purposes.
It holds plumbing systems.
It supports the entire weight of the building (Correct answer)

Correct answer: It supports the entire weight of the building

The foundation is the critical base upon which the entire structure rests. Its primary role is to transfer the building's weight evenly to the ground, preventing settling, shifting, and structural damage. A strong, well-maintained foundation is essential for the long-term stability, safety, and overall integrity of the home.

Question 68: According to the International Residential Code (IRC), which of the following situations requires the installation of safety glazing?

A glass panel in a cabinet door located in a kitchen.
An upper sash of a double-hung window in a second-floor bedroom.
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.
Glazing in a swinging door that separates a bedroom from a hallway. (Correct answer)

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

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

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

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 71: An inspector observes a double-tapped (two hoses connected to one fitting) washing machine supply hose connection at the valve. This is:

Acceptable if both hoses are braided stainless
Not a plumbing concern — only an electrical term
A deficiency; each supply connection requires its own dedicated valve (Correct answer)
Permitted if total flow does not exceed valve rating

Correct answer: A deficiency; each supply connection requires its own dedicated valve

Each washing machine supply hose should connect to its own dedicated shutoff valve; sharing a single valve connection is improper and creates reliability issues.

Question 72: What is the purpose of a weep screed at the base of stucco cladding?

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

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 73: What is the minimum recommended slope for asphalt shingles according to standard installation practices?

1:12
6:12
4:12
2:12 (Correct answer)

Correct answer: 2:12

Asphalt shingles require a minimum slope of 2:12 (2 inches of rise per 12 inches of run) for standard installation.

Question 74: What is the primary purpose of an equipment grounding conductor (EGC) in a branch circuit?

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

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 75: What is the purpose of a cricket (saddle) installed behind a chimney?

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

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 76: While inspecting a home built in 1935, an inspector observes electrical wiring consisting of single insulated conductors supported by white ceramic knobs and protected by ceramic tubes where they pass through wood framing. What is a primary safety concern associated with this type of wiring?

The ceramic components can release hazardous materials as they age.
It was designed to dissipate heat in open air and becomes a fire hazard if covered by thermal insulation. (Correct answer)
This wiring system is inherently prone to voltage surges.
The copper conductors are typically undersized for modern loads.

Correct answer: It was designed to dissipate heat in open air and becomes a fire hazard if covered by thermal insulation.

This describes knob-and-tube wiring. A major hazard is that the system was designed for heat to dissipate into open air. When modern thermal insulation is blown or packed around it, the wires can overheat, leading to the breakdown of their insulation and creating a significant fire risk. Other concerns include the lack of a ground wire and damage from improper modifications.

Question 77: 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
Galvanic corrosion from dissimilar metals in contact (Correct answer)
Condensation freeze-thaw cycling under the panels

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 78: Which of the following is a primary purpose of ventilating a traditional, unconditioned crawlspace?

To help remove moisture from the ground and prevent fungal growth. (Correct answer)
To allow radon gas to enter the home more easily.
To provide a suitable area for conditioned storage.
To warm the floors of the living space above during winter.

Correct answer: To help remove moisture from the ground and prevent fungal growth.

The primary goal of ventilating an unconditioned crawlspace is to allow moisture that evaporates from the soil to escape to the exterior. This cross-ventilation helps to reduce humidity levels within the crawlspace, which in turn minimizes the risk of fungal growth (mold), wood rot in the floor structure, and pest infestations.

Question 79: 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 only for circuits with more than four outlets
AFCI protection is required for all 120V, 15- and 20-amp branch circuits in bedrooms (Correct answer)

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 80: During an inspection, a bathroom exhaust fan duct is found to terminate inside the attic space, discharging moist air near a gable vent. According to modern building standards, what should the inspector report?

The gable vent provides sufficient ventilation for this type of discharge.
The duct is improperly terminated and must be extended to discharge directly to the building's exterior. (Correct answer)
The duct material should be changed from flexible to rigid metal.
This is an acceptable installation as long as it is within 5 feet of a vent.

Correct answer: The duct is improperly terminated and must be extended to discharge directly to the building's exterior.

Bathroom exhaust fans are designed to remove moisture-laden air from the home. Discharging this air into the attic, even near a vent, introduces excessive moisture that can lead to mold growth, wood rot, and reduced insulation effectiveness. Proper installation requires the duct to be routed continuously to the building's exterior, terminating through the roof, a wall, or a soffit.

Question 81: What condition is indicated when a toilet continues to run after the tank has fully refilled?

The supply stop valve is partially closed
The toilet requires a higher water pressure to operate
A faulty flapper or flush valve is allowing water to leak into the bowl (Correct answer)
The fill valve float is set too low

Correct answer: A faulty flapper or flush valve is allowing water to leak into the bowl

A continuously running toilet is most commonly caused by a worn or misaligned flapper that fails to seal the flush valve, allowing tank water to slowly drain into the bowl.

Question 82: 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?

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

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 83: While inspecting the junction of a roof plane and a vertical sidewall, an inspector should look for which type of flashing to be interwoven with the shingle courses?

Valley flashing
Counter-flashing
Drip edge
Step flashing (Correct answer)

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 84: 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?

Dew point deposition
Interstitial condensation by diffusion
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 85: 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 86: During an exterior inspection, which window condition requires reporting as a deficiency?

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

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

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

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 88: Which of the following is the most common cause for 'nail pops' appearing on interior drywall surfaces, especially in newer construction?

Corrosion of the metal fasteners due to high interior humidity.
The use of oversized drywall fasteners for the thickness of the board.
Vibrations from nearby construction or heavy traffic.
Shrinkage of the wood framing members as they dry out. (Correct answer)

Correct answer: Shrinkage of the wood framing members as they dry out.

The most common cause of nail or screw pops is the natural drying and shrinkage of wood framing lumber after construction. As the wood shrinks, the drywall remains stationary, and the fastener head can push through the joint compound, creating a 'pop.' While other factors can contribute, lumber shrinkage is the primary reason, particularly in the first few years of a new home.

Question 89: 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 home's interior is excessively dry due to the heating system.
The flooring was installed with an insufficient expansion gap at the perimeter walls.
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)

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 90: 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
100°F
120°F (Correct answer)
110°F

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 91: What is the primary concern when a driveway shows significant heaving near the garage apron?

Vehicle damage from uneven surface
Poor original concrete mix design
Driveway material has exceeded its service life
Potential freeze-thaw or tree root movement affecting adjacent foundation (Correct answer)

Correct answer: Potential freeze-thaw or tree root movement affecting adjacent foundation

Heaving near the garage apron can indicate frost or root intrusion that may also be affecting the garage foundation or slab.

Question 92: What is the standard InterNACHI recommendation when a home inspector cannot fully evaluate a component of the HVAC system?

Report it as inaccessible or unable to be inspected and recommend further evaluation by a qualified HVAC technician (Correct answer)
Mark it as satisfactory and move on
Skip it entirely and note it was inaccessible
Estimate its condition based on the age of the system

Correct answer: Report it as inaccessible or unable to be inspected and recommend further evaluation by a qualified HVAC technician

InterNACHI standards require inspectors to report any system or component that could not be inspected and to recommend specialist evaluation when warranted.

Question 93: 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
Improper mortar mix ratio
Normal thermal expansion

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

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

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 95: What condition does the term 'thermal bypass' describe in an insulated building assembly?

Radiant heat transfer across an air space adjacent to insulation
Air movement around or through insulation reducing its effectiveness (Correct answer)
Heat conducted through a framing member rather than insulation
A gap in insulation where two pieces fail to meet tightly

Correct answer: Air movement around or through insulation reducing its effectiveness

A thermal bypass occurs when air moves through or around insulation, carrying heat with it and significantly degrading the assembly's overall thermal performance.

Question 96: What is the recommended clearance between the bottom of an interior door and a finished floor to allow adequate air circulation for HVAC return air?

Exactly 1/8 inch to prevent drafts
No clearance is required for interior doors
Approximately ½ to ¾ inch (Correct answer)
At least 2 inches

Correct answer: Approximately ½ to ¾ inch

An undercut of approximately ½ to ¾ inch beneath interior doors allows return air to circulate back to the HVAC system when supply vents are in individual rooms.

Question 97: 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 ignore the wall as it is a landscaping feature.
To provide a cost estimate for replacing the wall.
To perform a structural analysis of the soil pressure behind 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 98: Which roof covering material has the longest typical service life under normal conditions?

Slate (Correct answer)
3-tab asphalt shingles
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 99: Which of the following is a common electrical issue found during home inspections?

Poor insulation of electrical wires.
Structural damage to walls.
Faulty plumbing.
Overloaded circuits (Correct answer)

Correct answer: Overloaded circuits

Overloaded circuits are a frequent electrical issue where too many appliances or devices draw power from a single circuit, exceeding its designated capacity. This can cause circuit breakers to trip, wiring to overheat, and poses a significant fire hazard. Identifying and addressing overloaded circuits is a critical finding during a home inspection to ensure safety.

Question 100: 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?

Missing H-clips only affect the fire rating of the roof assembly
The gaps indicate the sheathing is the wrong thickness for the rafter spacing
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 101: When inspecting exterior stairs, what baluster spacing deficiency is a safety hazard?

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

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

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

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

White (Correct answer)
Green
Red
Black

Correct answer: White

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

Question 104: Why should HVAC ducts be regularly cleaned?

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

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 105: 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?

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

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

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

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 107: Which condition in an attic most directly contributes to premature deterioration of roof shingles from below?

More than one attic access hatch
Presence of blown-in cellulose insulation
Inadequate attic ventilation causing excessive heat buildup (Correct answer)
Insufficient insulation thickness

Correct answer: Inadequate attic ventilation causing excessive heat buildup

Inadequate ventilation traps heat in the attic, which bakes shingles from below, accelerating thermal cracking and reducing shingle lifespan.

Question 108: What is the minimum height a masonry chimney must extend above a flat roof or a roof with a pitch less than 2:12?

4 feet above the roofline at all points
3 feet above the roof penetration point (Correct answer)
18 inches above the ridge line
2 feet above the highest point within 10 feet

Correct answer: 3 feet above the roof penetration point

Per the 2-3-10 rule, a chimney must extend at least 3 feet above the highest point where it passes through the roof.

Question 109: What does the term 'double-tapping' refer to in electrical panel inspections?

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

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 110: 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?

60-amp service is acceptable if no additions have been made
60-amp service is adequate for any modern home
The service capacity appears insufficient for the electrical loads present and evaluation by an electrician is recommended (Correct answer)
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 111: 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 112: Which of the following is a common defect found with older two-prong (ungrounded) receptacles?

They have no equipment grounding conductor, offering no protection against faults (Correct answer)
They are rated for less amperage than modern receptacles
They lack a neutral conductor
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 113: What exterior condition would prompt an inspector to recommend further evaluation by a licensed structural engineer?

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

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

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

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

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

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

Normal weathering on a new roof
Improper attic ventilation
The shingles are approaching end of useful life (Correct answer)
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 117: Which of the following best describes a 'floating neutral' condition in an electrical panel?

A neutral bus that is bonded to the ground bus in a sub-panel
A neutral bus not properly bonded, causing voltage imbalance (Correct answer)
A neutral wire connected to a grounding electrode
A neutral wire insulated with white tape

Correct answer: A neutral bus not properly bonded, causing voltage imbalance

A floating neutral occurs when the neutral is not properly connected, which can cause dangerous voltage imbalances on 240V circuits.

Question 118: Which of the following is a sign of a failing supply stop valve under a sink?

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

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

Extends at least 12 inches in front and 8 inches on each side
Extends at least 24 inches in all directions from the firebox opening
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 120: 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?

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

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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