CSLB Class B General Contractor's License - Building's Exam:
Core Trades (Part 2) practice exam, actual, realistic questions
and answers with complete solutions| latest version 2026.
3 inches - ANSWER: What is the minimum drain pipe size for the toilet in
a residential home?
B) Fire protection contractor - ANSWER: Who is licensed to install
residential fire sprinkler systems?
A) Plumbing contractor
B) Fire protection contractor
C) General Building contractor
D) Pipeline contractor
C) Clean the surface using a power tool - ANSWER: When brazing or
soldering gas pipes during the installation of water heaters, what is the
best way to prepare the pipe?
A) Clean it with water
B) Blow into the pipe using your lungs
C) Clean the surface using a power tool
D) Use a pressurized air canister
D) Endless rope lift - ANSWER: Which personal lift is not acceptable?
,A) Scissor
B) Boom
C) Manual
D) Endless rope lift
B) To soften PVC pipe before applying PVC cement - ANSWER: What is
the purpose of PVC primer?
A) To glue PVC pipes to other materials
B) To soften PVC pipe before applying PVC cement
C) To prevent electrical shock
D) To help solder conduit or piping
C) Flashing
(Leaks are most common when two surfaces meet or around
fenestration. Leaks are most prominent in valley flashing and
improperly installed window flashing.) - ANSWER: What is the most
common location to find a roof leak?
A) Attic
B) Shingles
C) Flashing
D) Collar tie
C) Pipe supports come into contact with metal piping
,(Mainly due to water hammer.) - ANSWER: What is the most common
reason for noise in piping when a water fixture is turned on or off?
A) Hot water was used
B) Cold water was used
C) Pipe supports come into contact with metal piping
D) The walls are not up to code causing pipe failure
C) Brass type - ANSWER: If you send your employee to purchase a 2-inch
water supply valve and they return with a 1.5-inch supply valve, then
what is the proper composition of the valve?
A) The casing must be made of plastic
B) The employee must return and purchase a wrought iron valve
C) Brass type
D) The connection must be silver and body made of iron
10 - ANSWER: When penetrating a roof with an exhaust, the exhaust must
be no closer than _____ feet to any air intake or openable window.
A) Class A - ANSWER: Which roof assembly has the best fire rating?
A) Class A
B) Class B
C) Class I
D) Class III
, D) Use of materials that are compatible with the type of pipe and fitting
materials - ANSWER: What does material compatibility refer to when
installing alternate water sources in existing plumbing systems?
A) Plumbing fixtures have to come from the same manufacturer
B) Only the couplings must be made of metal
C) All plumbing connections must be soldered or brazed
D) Use of materials that are compatible with the type of pipe and fitting
materials
C) Weather seal, weather strip, and apply caulking - ANSWER: When you
have a gap in the building envelope, what do you do to prevent air
leakage?
A) Stuff insulation into gaps
B) Put caulking in and around the gaps
C) Weather seal, weather strip, and apply caulking
D) Nothing, all buildings require air leakage
18 inches - ANSWER: In order to protect a water heater from damage,
what is the minimum height it should be from the floor of a garage?
4
(According to the California Plumbing Code, the vertical piping between
two consecutive inlet levels shall be considered a wet-vented section.
Each wet-vented section shall be not less than one pipe size exceeding
the required minimum waste pipe size of the upper fixture or shall be
one pipe size exceeding the required minimum pipe size for the sum of
the fixture units served by such wet-vented section, whichever is
Core Trades (Part 2) practice exam, actual, realistic questions
and answers with complete solutions| latest version 2026.
3 inches - ANSWER: What is the minimum drain pipe size for the toilet in
a residential home?
B) Fire protection contractor - ANSWER: Who is licensed to install
residential fire sprinkler systems?
A) Plumbing contractor
B) Fire protection contractor
C) General Building contractor
D) Pipeline contractor
C) Clean the surface using a power tool - ANSWER: When brazing or
soldering gas pipes during the installation of water heaters, what is the
best way to prepare the pipe?
A) Clean it with water
B) Blow into the pipe using your lungs
C) Clean the surface using a power tool
D) Use a pressurized air canister
D) Endless rope lift - ANSWER: Which personal lift is not acceptable?
,A) Scissor
B) Boom
C) Manual
D) Endless rope lift
B) To soften PVC pipe before applying PVC cement - ANSWER: What is
the purpose of PVC primer?
A) To glue PVC pipes to other materials
B) To soften PVC pipe before applying PVC cement
C) To prevent electrical shock
D) To help solder conduit or piping
C) Flashing
(Leaks are most common when two surfaces meet or around
fenestration. Leaks are most prominent in valley flashing and
improperly installed window flashing.) - ANSWER: What is the most
common location to find a roof leak?
A) Attic
B) Shingles
C) Flashing
D) Collar tie
C) Pipe supports come into contact with metal piping
,(Mainly due to water hammer.) - ANSWER: What is the most common
reason for noise in piping when a water fixture is turned on or off?
A) Hot water was used
B) Cold water was used
C) Pipe supports come into contact with metal piping
D) The walls are not up to code causing pipe failure
C) Brass type - ANSWER: If you send your employee to purchase a 2-inch
water supply valve and they return with a 1.5-inch supply valve, then
what is the proper composition of the valve?
A) The casing must be made of plastic
B) The employee must return and purchase a wrought iron valve
C) Brass type
D) The connection must be silver and body made of iron
10 - ANSWER: When penetrating a roof with an exhaust, the exhaust must
be no closer than _____ feet to any air intake or openable window.
A) Class A - ANSWER: Which roof assembly has the best fire rating?
A) Class A
B) Class B
C) Class I
D) Class III
, D) Use of materials that are compatible with the type of pipe and fitting
materials - ANSWER: What does material compatibility refer to when
installing alternate water sources in existing plumbing systems?
A) Plumbing fixtures have to come from the same manufacturer
B) Only the couplings must be made of metal
C) All plumbing connections must be soldered or brazed
D) Use of materials that are compatible with the type of pipe and fitting
materials
C) Weather seal, weather strip, and apply caulking - ANSWER: When you
have a gap in the building envelope, what do you do to prevent air
leakage?
A) Stuff insulation into gaps
B) Put caulking in and around the gaps
C) Weather seal, weather strip, and apply caulking
D) Nothing, all buildings require air leakage
18 inches - ANSWER: In order to protect a water heater from damage,
what is the minimum height it should be from the floor of a garage?
4
(According to the California Plumbing Code, the vertical piping between
two consecutive inlet levels shall be considered a wet-vented section.
Each wet-vented section shall be not less than one pipe size exceeding
the required minimum waste pipe size of the upper fixture or shall be
one pipe size exceeding the required minimum pipe size for the sum of
the fixture units served by such wet-vented section, whichever is
