ICC Residential Building Inspector (B1) Certification
Exam 2026 (2 Sets) | Verified Questions and Detailed
Answers
OVERVIEW DESCRIPTION:
This comprehensive collection of multiple-choice questions is designed for the ICC Residential
Building Inspector (B1) Certification Exam. The questions are organized into two complete sets
of 60 questions each, covering all major content areas of the exam including wall construction,
footings and foundations, floor and roof framing, building planning, public safety features, and
code administration. Each question includes the correct answer and a concise expert rationale
referencing specific sections of the International Residential Code (IRC), providing candidates
with both knowledge validation and code interpretation practice essential for exam success.
SET 1
QUESTION 1
A building inspector is reviewing site grading around a new foundation. What is the
minimum required fall of the finished grade away from the foundation wall?
A. 2 inches within the first 5 feet
B. 4 inches within the first 8 feet
C. 6 inches within the first 10 feet
D. 1 inch per foot for the first 6 feet
CORRECT ANSWER: C
EXPERT RATIONALE: IRC R401.3 requires that the ground immediately adjacent to the
foundation be sloped a minimum of 6 inches within the first 10 feet to ensure proper
drainage away from the structure.
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QUESTION 2
For a wood-framed exterior bearing wall, what is the maximum allowable spacing for
studs typically permitted when supporting two floors and a roof?
A. 12 inches on center
B. 16 inches on center
C. 19.2 inches on center
D. 24 inches on center
CORRECT ANSWER: B
EXPERT RATIONALE: IRC Table R602.3(5) specifies that for bearing walls supporting
two floors and a roof, the maximum stud spacing is typically 16 inches on center for
most grades and species.
QUESTION 3
Where are smoke alarms required to be located in relation to bedrooms in a new one-
family dwelling?
A. Only inside each bedroom
B. Only in the hallway outside of bedrooms
C. Both inside each bedroom and outside each separate sleeping area
D. On every level, but not required inside the bedrooms
CORRECT ANSWER: C
EXPERT RATIONALE: IRC R314.3 requires smoke alarms to be installed in each
sleeping room, outside each separate sleeping area in the immediate vicinity of the
bedrooms, and on every level of the home.
QUESTION 4
What is the minimum required thickness for a plain concrete footing supporting a one-
story dwelling with a 2,500 psi compressive strength?
A. 4 inches
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B. 6 inches
C. 8 inches
D. 12 inches
CORRECT ANSWER: B
EXPERT RATIONALE: IRC Table R403.1(1) specifies that the minimum thickness for a
plain concrete footing is 6 inches, though it may need to increase based on the
projection from the foundation wall.
QUESTION 5
An inspector is verifying floor joist spans. According to the IRC, what live load must be
used for designing floors in sleeping areas?
A. 20 psf
B. 30 psf
C. 40 psf
D. 50 psf
CORRECT ANSWER: B
EXPERT RATIONALE: IRC Table R301.5 assigns a minimum uniformly distributed live
load of 30 psf for sleeping rooms, while other living areas require 40 psf.
QUESTION 6
What is the maximum spacing for corrugated galvanized steel wall ties when attaching
masonry veneer to a wood-framed wall?
A. 12 inches vertical by 24 inches horizontal
B. 16 inches vertical by 24 inches horizontal
C. 16 inches vertical by 32 inches horizontal
D. 24 inches vertical by 24 inches horizontal
CORRECT ANSWER: B
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EXPERT RATIONALE: IRC Table R703.8.4 specifies that for masonry veneer, corrugated
sheet metal ties shall be spaced at a maximum of 16 inches vertically and 24 inches
horizontally.
QUESTION 7
For a stairway, what is the maximum permitted riser height and minimum tread depth?
A. Maximum riser 8 inches, minimum tread 9 inches
B. Maximum riser 7.75 inches, minimum tread 10 inches
C. Maximum riser 7.5 inches, minimum tread 10.5 inches
D. Maximum riser 7 inches, minimum tread 11 inches
CORRECT ANSWER: B
EXPERT RATIONALE: IRC R311.7.4 and R311.7.5 specify that the maximum riser height is
7-3/4 inches and the minimum tread depth is 10 inches.
QUESTION 8
What is the minimum nominal size for a header spanning 5 feet in an exterior bearing
wall supporting one floor and a roof?
A. 2-2x4
B. 2-2x6
C. 2-2x8
D. 2-2x10
CORRECT ANSWER: B
EXPERT RATIONALE: According to IRC Table R602.7(1), for a building width of 24 feet, a
5-foot span opening requires a header of at least two 2x6s.
QUESTION 9
Where is fireblocking typically required in wood-framed construction?
A. Only in the attic space
B. At the top and bottom of each stairwell