NEWEST CERTIFIED RESIDENTIAL BUILDING
INSPECTOR (RBI) CERTIFICATION EXAM
OFFERED BY INTERNATIONAL CODE COUNCIL
(ICC) | COMPLETE EXAM Q&A WITH
RATIONALES
1. A new house is being built with 2x4 wood studs at
16 inches on center. According to the International
Residential Code (IRC), what is the maximum
allowable notch depth in the end of a ceiling joist?
A) 1/4 of the joist depth
B) 1/3 of the joist depth
C) 1/2 of the joist depth
D) 5/8 of the joist depth
Correct answer: A
Rationale: IRC Table R502.8 limits notches at the end
of a joist to 1/4 of the joist depth. Notches in the top
or bottom are limited to 1/6 of the depth.
2. The minimum required size for a bedroom egress
window is 5.7 square feet of net clear opening. The
window is 36 inches wide and opens fully. What is the
minimum height required to meet this opening?
,A) 18 inches
B) 24 inches
C) 28 inches
D) 36 inches
Correct answer: B
Rationale: 5.7 sq ft = 820.8 sq in. 820.8 ÷ 36 inches =
22.8 inches, so 24 inches is the minimum height
needed, which also exceeds the 24-inch minimum
height requirement.
3. An inspector finds a guardrail on a residential deck
with a horizontal span of 8 feet. The intermediate
balusters are spaced 5 inches apart. The deck is 30
inches above grade. Which IRC requirement is
violated?
A) The guardrail height is too low
B) The baluster spacing exceeds 4 inches
C) The horizontal span of 8 feet requires intermediate
support
D) The guardrail is required at 24 inches, not 30
inches
Correct answer: B
,Rationale: IRC R312.1.2 requires that intermediate
balusters be spaced so that a 4-inch sphere cannot
pass through. A 5-inch spacing violates this.
4. During a framing inspection, the inspector notes
that an 8-foot-long header above a garage door is
supported by a single jack stud at each end. The
header bears on a 2x4 wall. According to IRC, what is
the minimum number of jack studs required?
A) One
B) Two
C) Three
D) Four
Correct answer: B
Rationale: IRC Table R602.7 requires a minimum of
two jack studs for spans exceeding 6 feet, depending
on load.
5. A single-family home has a 22-foot clear-span floor
truss system. The truss manufacturer's drawing is
not available on site. What is the inspector's most
appropriate action?
A) Approve the framing because the span is within
typical limits
, B) Require the truss manufacturer's drawing and
engineering calculations
C) Measure the truss chords to determine if they
meet prescriptive sizes
D) Reject the entire framing system
Correct answer: B
Rationale: Trusses are engineered components. The
installation drawing and engineering calculations
must be on site for inspection.
6. An attic scuttle hole is located in a second-floor
hallway. The attic is used only for storage. The
opening measures 22 inches by 30 inches. What IRC
requirement is most likely violated?
A) Minimum rough opening for attic access
B) Minimum size of landing at the top of the attic
stairs
C) Minimum headroom clearance in the attic
D) Fire protection rating of the scuttle hole cover
Correct answer: D
Rationale: IRC R807.1 requires that attic access
openings in dwelling units be covered with a material
having at least a 1-hour fire resistance rating if the
opening is located in a required corridor or area.
INSPECTOR (RBI) CERTIFICATION EXAM
OFFERED BY INTERNATIONAL CODE COUNCIL
(ICC) | COMPLETE EXAM Q&A WITH
RATIONALES
1. A new house is being built with 2x4 wood studs at
16 inches on center. According to the International
Residential Code (IRC), what is the maximum
allowable notch depth in the end of a ceiling joist?
A) 1/4 of the joist depth
B) 1/3 of the joist depth
C) 1/2 of the joist depth
D) 5/8 of the joist depth
Correct answer: A
Rationale: IRC Table R502.8 limits notches at the end
of a joist to 1/4 of the joist depth. Notches in the top
or bottom are limited to 1/6 of the depth.
2. The minimum required size for a bedroom egress
window is 5.7 square feet of net clear opening. The
window is 36 inches wide and opens fully. What is the
minimum height required to meet this opening?
,A) 18 inches
B) 24 inches
C) 28 inches
D) 36 inches
Correct answer: B
Rationale: 5.7 sq ft = 820.8 sq in. 820.8 ÷ 36 inches =
22.8 inches, so 24 inches is the minimum height
needed, which also exceeds the 24-inch minimum
height requirement.
3. An inspector finds a guardrail on a residential deck
with a horizontal span of 8 feet. The intermediate
balusters are spaced 5 inches apart. The deck is 30
inches above grade. Which IRC requirement is
violated?
A) The guardrail height is too low
B) The baluster spacing exceeds 4 inches
C) The horizontal span of 8 feet requires intermediate
support
D) The guardrail is required at 24 inches, not 30
inches
Correct answer: B
,Rationale: IRC R312.1.2 requires that intermediate
balusters be spaced so that a 4-inch sphere cannot
pass through. A 5-inch spacing violates this.
4. During a framing inspection, the inspector notes
that an 8-foot-long header above a garage door is
supported by a single jack stud at each end. The
header bears on a 2x4 wall. According to IRC, what is
the minimum number of jack studs required?
A) One
B) Two
C) Three
D) Four
Correct answer: B
Rationale: IRC Table R602.7 requires a minimum of
two jack studs for spans exceeding 6 feet, depending
on load.
5. A single-family home has a 22-foot clear-span floor
truss system. The truss manufacturer's drawing is
not available on site. What is the inspector's most
appropriate action?
A) Approve the framing because the span is within
typical limits
, B) Require the truss manufacturer's drawing and
engineering calculations
C) Measure the truss chords to determine if they
meet prescriptive sizes
D) Reject the entire framing system
Correct answer: B
Rationale: Trusses are engineered components. The
installation drawing and engineering calculations
must be on site for inspection.
6. An attic scuttle hole is located in a second-floor
hallway. The attic is used only for storage. The
opening measures 22 inches by 30 inches. What IRC
requirement is most likely violated?
A) Minimum rough opening for attic access
B) Minimum size of landing at the top of the attic
stairs
C) Minimum headroom clearance in the attic
D) Fire protection rating of the scuttle hole cover
Correct answer: D
Rationale: IRC R807.1 requires that attic access
openings in dwelling units be covered with a material
having at least a 1-hour fire resistance rating if the
opening is located in a required corridor or area.
