National Home Inspector Exam
questions and answers
Stud ✔✔(1) a grade of lumber used in wall construction rated below #2 grade and
approximately equal to #3 grade; (2) a vertical structural member in a wall.
Stud (cripple) ✔✔a less than full height vertical structural member usually found under
windows and in partial height walls.
Stud (jack) ✔✔a less than full height vertical structural member placed under a header
to provide bearing support for the header.
Stud (king) ✔✔a full height vertical structural member placed on the sides of a header.
Tension force (load) ✔✔the force that pulls or stretches a structural member. A beam
under a vertical load is under tension on the bottom. Contrast Compression.
Townhouse ✔✔a single family attached dwelling with all of the following: (1) three or
more dwellings in one building, (2) dwelling extends from the foundation to the roof, (3)
a yard or public way on at least two sides. A townhouse is a type of building, not a form
of real property ownership.
Dew point (temperature) ✔✔the temperature at which water vapor in the air may
condense into liquid water. A higher dew point temperature that the air contains more
water vapor.
Fenestration ✔✔openings in the wall and roof of a house such as windows, doors, and
skylights.
✔✔
✔✔Ampacity ✔✔The maximum current, in amperes, that a conductor can carry
continuously under the conditions of use without exceeding its temperature rating.
American Wire Gauge (AWG) ✔✔an standard method of denoting the diameter of
electrically conducting wire
Bonding ✔✔The process of connecting, both physically and electrically, metal
components of the electrical system that are not intended to carry electrical current to
provide a low resistance return path to the circuit breaker or fuse to clear ground faults;
bonding is an elecsafety system. system.
,Branch Circuit ✔✔Conductors that begin at a circuit breaker or fuse and serve one or
more oulets.
Branch Circuit, multiwire ✔✔A branch circuit in which two energized conductors share
one neutral, examples can include clothes dryers, ranges and other cooking appliances,
and split-wire receptacle circuits, 240 volt water heaters and condensers for air
conditioners and heat pumps are not usually branch circuits.
Bus (buss, busbar) ✔✔the heavy, rigid metal part of a panelboard on which circuit
breakers or fuses are mounted; sometimes used to describe metal terminals to which
the neutral and equipment grounding conductors (EGCs) are connected.
Cable ✔✔two or more conductors encased in sheathing; examples include non-metallic
sheathed cable (Brand Romex) and armored cable (Brand BX)
circuit breaker ✔✔overcurrent protection device (OPD)
Conductor ✔✔a material, such as copper or aluminum, that permits electricity to flow
with low resistance, wires are conductors.
Current ✔✔the amount of electricity in a circuit. Unit of measure is the ampere (amp);
expressed as I in Ohm's Law and Watt's Law equation.
Dead front cover ✔✔a panel that is removed to gain access to the energized
components inside an enclosure; the dead front cover is usually behind a door that must
be swung or lifted to gain access to the dead front cover.
EGC ✔✔Equipment grounding conductor
Enclosure (electrical) ✔✔a case or cabinet intended to prevent accidental contact with
energized parts, a panelboard is housed inside an enclosure.
Feeder conductors ✔✔conductors from the service equipment or from a panelboard that
supply electricity to another panelboard such as a subpanel.
Fuse ✔✔Overcurrent protection device (OPD)
Grounded ✔✔a conductor that is intentionally connected to earth; this describes what is
often called the neutral conductor.
grounding ✔✔providing an intentional connection to earth, grounding provides an
alternate path for current to return to its source; in an electrical power system, the
source is the utilities transformer and ultimately power plant. See grounding electrode
and grounding electrode conductor (GEC).
, Grounding Conductor, Equipment (EGC) ✔✔a bare or insulated conductor that provides
a ground fault current path (a bonding connection) for equipment with metal cases and
parts; these have been installed in most house branch circuit wiring since around 1960.
grounding electrode ✔✔metal that is in direct contact with the earth and serves as the
electrical system grounding connection; examples include copper coated steel rods,
galvanized steel pipes, water service and well pipes, and reinforcing steel encased
footings.
grounding electrode conductor (GEC) ✔✔a conductor that runs between the grounding
electrode and an accessible point downstream from where the grounded service
entrance conductor connects to the service drop or lateral; the GEC connection is
usually at the service equipment.
Ground fault ✔✔an event that occurs when metal that should not conduct electricity
(such as a metal water pipe) becomes energized; if the metal is properly bonded,
current flow should increase in the circuit and trip the circuit breaker or fuse.
Ground Fault Circuit Interrupter (GFCI) ✔✔a circuit breaker or receptacle that detects a
ground fault by monitoring the imbalance in current flow between the energized and
neutral conductors and stops current flow kopens the circuit) when a ground fault is
detected.
Joules Law ✔✔a formula for calculating heat in an electrical circuit expressed as Heat =
Current▪︎2 X Resistance X Time.
Knockouts ✔✔stamped openings in an enclosure where conduit or cable clamps are
installed to secure conductors or cables. See Tabs (twistouts).
Load Center ✔✔See Panel (panelboard, load center)
Lug ✔✔a connection point where conductors are inserted and secured; examples
include the connection points on panelboards for service entrance and feeder
conductors, on terminal bars for neutral and EGCs, and on circuit breakers for branch
circuit conductors.
Ohm's Law and Watt's Law ✔✔expressions of the relationship between current, voltage,
power, and resistance; expressed as Power = Volts X Amps and Resistance =
Volts/Amps
Outlet ✔✔a place where current is taken for use; examples include receptacles, light
fixtures, and connections at electrical appliances such as water heaters.
questions and answers
Stud ✔✔(1) a grade of lumber used in wall construction rated below #2 grade and
approximately equal to #3 grade; (2) a vertical structural member in a wall.
Stud (cripple) ✔✔a less than full height vertical structural member usually found under
windows and in partial height walls.
Stud (jack) ✔✔a less than full height vertical structural member placed under a header
to provide bearing support for the header.
Stud (king) ✔✔a full height vertical structural member placed on the sides of a header.
Tension force (load) ✔✔the force that pulls or stretches a structural member. A beam
under a vertical load is under tension on the bottom. Contrast Compression.
Townhouse ✔✔a single family attached dwelling with all of the following: (1) three or
more dwellings in one building, (2) dwelling extends from the foundation to the roof, (3)
a yard or public way on at least two sides. A townhouse is a type of building, not a form
of real property ownership.
Dew point (temperature) ✔✔the temperature at which water vapor in the air may
condense into liquid water. A higher dew point temperature that the air contains more
water vapor.
Fenestration ✔✔openings in the wall and roof of a house such as windows, doors, and
skylights.
✔✔
✔✔Ampacity ✔✔The maximum current, in amperes, that a conductor can carry
continuously under the conditions of use without exceeding its temperature rating.
American Wire Gauge (AWG) ✔✔an standard method of denoting the diameter of
electrically conducting wire
Bonding ✔✔The process of connecting, both physically and electrically, metal
components of the electrical system that are not intended to carry electrical current to
provide a low resistance return path to the circuit breaker or fuse to clear ground faults;
bonding is an elecsafety system. system.
,Branch Circuit ✔✔Conductors that begin at a circuit breaker or fuse and serve one or
more oulets.
Branch Circuit, multiwire ✔✔A branch circuit in which two energized conductors share
one neutral, examples can include clothes dryers, ranges and other cooking appliances,
and split-wire receptacle circuits, 240 volt water heaters and condensers for air
conditioners and heat pumps are not usually branch circuits.
Bus (buss, busbar) ✔✔the heavy, rigid metal part of a panelboard on which circuit
breakers or fuses are mounted; sometimes used to describe metal terminals to which
the neutral and equipment grounding conductors (EGCs) are connected.
Cable ✔✔two or more conductors encased in sheathing; examples include non-metallic
sheathed cable (Brand Romex) and armored cable (Brand BX)
circuit breaker ✔✔overcurrent protection device (OPD)
Conductor ✔✔a material, such as copper or aluminum, that permits electricity to flow
with low resistance, wires are conductors.
Current ✔✔the amount of electricity in a circuit. Unit of measure is the ampere (amp);
expressed as I in Ohm's Law and Watt's Law equation.
Dead front cover ✔✔a panel that is removed to gain access to the energized
components inside an enclosure; the dead front cover is usually behind a door that must
be swung or lifted to gain access to the dead front cover.
EGC ✔✔Equipment grounding conductor
Enclosure (electrical) ✔✔a case or cabinet intended to prevent accidental contact with
energized parts, a panelboard is housed inside an enclosure.
Feeder conductors ✔✔conductors from the service equipment or from a panelboard that
supply electricity to another panelboard such as a subpanel.
Fuse ✔✔Overcurrent protection device (OPD)
Grounded ✔✔a conductor that is intentionally connected to earth; this describes what is
often called the neutral conductor.
grounding ✔✔providing an intentional connection to earth, grounding provides an
alternate path for current to return to its source; in an electrical power system, the
source is the utilities transformer and ultimately power plant. See grounding electrode
and grounding electrode conductor (GEC).
, Grounding Conductor, Equipment (EGC) ✔✔a bare or insulated conductor that provides
a ground fault current path (a bonding connection) for equipment with metal cases and
parts; these have been installed in most house branch circuit wiring since around 1960.
grounding electrode ✔✔metal that is in direct contact with the earth and serves as the
electrical system grounding connection; examples include copper coated steel rods,
galvanized steel pipes, water service and well pipes, and reinforcing steel encased
footings.
grounding electrode conductor (GEC) ✔✔a conductor that runs between the grounding
electrode and an accessible point downstream from where the grounded service
entrance conductor connects to the service drop or lateral; the GEC connection is
usually at the service equipment.
Ground fault ✔✔an event that occurs when metal that should not conduct electricity
(such as a metal water pipe) becomes energized; if the metal is properly bonded,
current flow should increase in the circuit and trip the circuit breaker or fuse.
Ground Fault Circuit Interrupter (GFCI) ✔✔a circuit breaker or receptacle that detects a
ground fault by monitoring the imbalance in current flow between the energized and
neutral conductors and stops current flow kopens the circuit) when a ground fault is
detected.
Joules Law ✔✔a formula for calculating heat in an electrical circuit expressed as Heat =
Current▪︎2 X Resistance X Time.
Knockouts ✔✔stamped openings in an enclosure where conduit or cable clamps are
installed to secure conductors or cables. See Tabs (twistouts).
Load Center ✔✔See Panel (panelboard, load center)
Lug ✔✔a connection point where conductors are inserted and secured; examples
include the connection points on panelboards for service entrance and feeder
conductors, on terminal bars for neutral and EGCs, and on circuit breakers for branch
circuit conductors.
Ohm's Law and Watt's Law ✔✔expressions of the relationship between current, voltage,
power, and resistance; expressed as Power = Volts X Amps and Resistance =
Volts/Amps
Outlet ✔✔a place where current is taken for use; examples include receptacles, light
fixtures, and connections at electrical appliances such as water heaters.
