1 | Page
Residential Plumbing Questions and
Answers Latest 2026
T/F: This course only addresses code-related violations
regarding plumbing fixtures. Ans: False
"Plumbing" comes from the Latin word "plumbum," which
means ___________.
"toilet"
"water system"
"lead" Ans: "lead"
T/F: Contamination can affect water's potability. Ans:
True
According to the InterNACHI Standards of Practice, the
inspector is required to _______ all the toilets.
unbolt and lift
use
flush
clean Ans: flush
Determining the location of the main water supply shut-
off valve is _____ the scope of a home inspection.
© 2025 All rights reserved
, 2 | Page
not part of
beyond
within Ans: within
T/F: The inspector must examine a home for
polybutylene plumbing. Ans: False
Acrylonitrile butadiene styrene is sometimes abbreviated
as:
ABS
A-S Level
Butadiene Mix Ans: ABS
The unobstructed vertical distance through the free
atmosphere between an outlet and the rim best describes
___________.
an air gap in the drainage system
a connection problem
an indirect drainage space
the best way to vent contaminated water Ans: an air gap
in the drainage system
Air-admittance valves protect traps from _________.
© 2025 All rights reserved
, 3 | Page
clogging
leaking
admitting air into the vent pipe
siphonage
admitting water into the drainpipe Ans: siphonage
Where do gasses escape a sanitary drainage system?
a supply vent
a vent stack
an air-admittance valve
a sewer drainpipe Ans: a vent stack
A lavatory is __________.
a bathroom with a toilet but no sink
any type of sink
a bathroom or washroom sink Ans: a bathroom or
washroom sink
An anchoring ring that is secured to the floor is a
__________.
wax ring device
© 2025 All rights reserved
Residential Plumbing Questions and
Answers Latest 2026
T/F: This course only addresses code-related violations
regarding plumbing fixtures. Ans: False
"Plumbing" comes from the Latin word "plumbum," which
means ___________.
"toilet"
"water system"
"lead" Ans: "lead"
T/F: Contamination can affect water's potability. Ans:
True
According to the InterNACHI Standards of Practice, the
inspector is required to _______ all the toilets.
unbolt and lift
use
flush
clean Ans: flush
Determining the location of the main water supply shut-
off valve is _____ the scope of a home inspection.
© 2025 All rights reserved
, 2 | Page
not part of
beyond
within Ans: within
T/F: The inspector must examine a home for
polybutylene plumbing. Ans: False
Acrylonitrile butadiene styrene is sometimes abbreviated
as:
ABS
A-S Level
Butadiene Mix Ans: ABS
The unobstructed vertical distance through the free
atmosphere between an outlet and the rim best describes
___________.
an air gap in the drainage system
a connection problem
an indirect drainage space
the best way to vent contaminated water Ans: an air gap
in the drainage system
Air-admittance valves protect traps from _________.
© 2025 All rights reserved
, 3 | Page
clogging
leaking
admitting air into the vent pipe
siphonage
admitting water into the drainpipe Ans: siphonage
Where do gasses escape a sanitary drainage system?
a supply vent
a vent stack
an air-admittance valve
a sewer drainpipe Ans: a vent stack
A lavatory is __________.
a bathroom with a toilet but no sink
any type of sink
a bathroom or washroom sink Ans: a bathroom or
washroom sink
An anchoring ring that is secured to the floor is a
__________.
wax ring device
© 2025 All rights reserved
