Free ICC B1 Practice Test: 30 Questions with IRC Answers
This free ICC B1 practice test has 30 original, unofficial questions, each labeled with the IRC edition used for its answer. It is a mixed 2021/2024 study set—not a full exam for either edition; work with the specified IRC open so you practice finding rules, not just recalling them.
Practice questions
Question 1 of 30 · Code Administration · 2024 IRC
A homeowner plans a one-story detached storage shed with 180 sq ft of floor area. It is not a storm shelter, and the jurisdiction hasn't amended the 2024 IRC's permit exemptions. Which statement is correct?
- A. A building permit is required because every accessory structure needs one
- B. The shed is exempt only if it's under 120 sq ft
- C. The shed is exempt only if it's under 10 ft tall
- D. The shed is exempt from a building permit because its floor area doesn't exceed 200 sq ft
Show answer and explanation for Question 1 of 30
Correct answer: D. The shed is exempt from a building permit because its floor area doesn't exceed 200 sq ft
The 2024 IRC exemption covers one-story detached accessory structures up to 200 sq ft, other than storm shelters. A overlooks that exemption; B substitutes a 120-sq-ft threshold that is not the one in this provision; C substitutes a height test. Two things the exemption doesn't do: it doesn't excuse the work from meeting the code, and it doesn't override a local amendment.
Find it: Index → "Permits" → work exempt from permit. Code section: 2024 IRC R105.2, Building item 1.
Source: City of Benson: 2024 IRC R105.2 excerpt — PDF p. 1, R105.2, Building item 1
Correct answer: D. The shed is exempt from a building permit because its floor area doesn't exceed 200 sq ft
The 2024 IRC exemption covers one-story detached accessory structures up to 200 sq ft, other than storm shelters. A overlooks that exemption; B substitutes a 120-sq-ft threshold that is not the one in this provision; C substitutes a height test. Two things the exemption doesn't do: it doesn't excuse the work from meeting the code, and it doesn't override a local amendment.
Find it: Index → "Permits" → work exempt from permit. Code section: 2024 IRC R105.2, Building item 1.
Source: City of Benson: 2024 IRC R105.2 excerpt — PDF p. 1, R105.2, Building item 1
Question 2 of 30 · Code Administration · 2024 IRC
All four projects have independent means of egress and otherwise fit the residential building types listed in the IRC. Which is outside its ordinary scope because of its number of stories above grade plane?
- A. A detached single-family dwelling with four stories above grade plane
- B. A detached single-family dwelling with three stories above grade plane
- C. A two-family dwelling with two stories above grade plane
- D. A townhouse building with two stories above grade plane
Show answer and explanation for Question 2 of 30
Correct answer: A. A detached single-family dwelling with four stories above grade plane
The IRC's ordinary scope stops at three stories above grade plane. A has four, so it exceeds that limit. B reaches the limit without exceeding it; C and D are below it. Count stories above grade plane as the question specifies—not simply every floor a building contains. This scope test does not approve the rest of a building's design.
Find it: Chapter 1 → Scope and general requirements → scope. Code section: 2024 IRC R101.2.
Correct answer: A. A detached single-family dwelling with four stories above grade plane
The IRC's ordinary scope stops at three stories above grade plane. A has four, so it exceeds that limit. B reaches the limit without exceeding it; C and D are below it. Count stories above grade plane as the question specifies—not simply every floor a building contains. This scope test does not approve the rest of a building's design.
Find it: Chapter 1 → Scope and general requirements → scope. Code section: 2024 IRC R101.2.
Building Planning
Question 3 of 30 · Building Planning · 2024 IRC
A proposed bedroom with a flat ceiling measures 7 ft 6 in × 9 ft. Does it meet the IRC minimum size for a habitable room?
- A. Yes, because both dimensions are at least 7 ft
- B. No, because habitable rooms must be at least 8 ft in every horizontal direction
- C. No, because its floor area is 67.5 sq ft, below the 70 sq ft minimum
- D. Yes, because only one room in a dwelling has a minimum floor area
Show answer and explanation for Question 3 of 30
Correct answer: C. No, because its floor area is 67.5 sq ft, below the 70 sq ft minimum
This bedroom needs both at least 70 sq ft of floor area and at least 7 ft in any horizontal dimension. This room passes the 7-ft test (A only checks that part) but fails on area: 7.5 × 9 = 67.5 sq ft. B uses the wrong dimension (it's 7 ft, not 8). D would let this bedroom escape an area requirement it must meet.
Math: 7.5 ft × 9 ft = 67.5 sq ft < 70 sq ft
Find it: Index → "Room area" (minimum room areas). Code section: 2024 IRC R312.1 and R312.2.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 64 (PDF p. 6)
Correct answer: C. No, because its floor area is 67.5 sq ft, below the 70 sq ft minimum
This bedroom needs both at least 70 sq ft of floor area and at least 7 ft in any horizontal dimension. This room passes the 7-ft test (A only checks that part) but fails on area: 7.5 × 9 = 67.5 sq ft. B uses the wrong dimension (it's 7 ft, not 8). D would let this bedroom escape an area requirement it must meet.
Math: 7.5 ft × 9 ft = 67.5 sq ft < 70 sq ft
Find it: Index → "Room area" (minimum room areas). Code section: 2024 IRC R312.1 and R312.2.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 64 (PDF p. 6)
Question 4 of 30 · Building Planning · 2024 IRC
A 150 sq ft habitable room relies on windows for natural light. No artificial-light alternative or adjoining-room allowance applies. What is the minimum glazed area?
- A. 6 sq ft
- B. 7.5 sq ft
- C. 12 sq ft
- D. 15 sq ft
Show answer and explanation for Question 4 of 30
Correct answer: C. 12 sq ft
Glazing for natural light must be at least 8% of the room's floor area: 150 × 0.08 = 12 sq ft. A is 4%, which is the openable area required for natural ventilation, a separate requirement. B is 5%, and D is 10%; neither is a code figure for this.
Math: 150 sq ft × 0.08 = 12 sq ft
Find it: Index → "Light, natural". Code section: 2024 IRC R325.1.1; R325.1.2 for the ventilation comparison.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 61 (PDF p. 3)
Correct answer: C. 12 sq ft
Glazing for natural light must be at least 8% of the room's floor area: 150 × 0.08 = 12 sq ft. A is 4%, which is the openable area required for natural ventilation, a separate requirement. B is 5%, and D is 10%; neither is a code figure for this.
Math: 150 sq ft × 0.08 = 12 sq ft
Find it: Index → "Light, natural". Code section: 2024 IRC R325.1.1; R325.1.2 for the ventilation comparison.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 61 (PDF p. 3)
Footings and Foundations
Question 5 of 30 · Footings and Foundations · 2024 IRC
For an ordinary prescriptive concrete footing supporting a dwelling, which bearing material meets the IRC's stated foundation-base requirement?
- A. Undisturbed natural soil or compacted engineered fill
- B. Topsoil containing roots and vegetation
- C. Loose, uncompacted excavation backfill
- D. Construction debris covered with a thin layer of sand
Show answer and explanation for Question 5 of 30
Correct answer: A. Undisturbed natural soil or compacted engineered fill
The footing must bear on undisturbed natural soil or compacted engineered fill. B leaves organic material in the bearing area; C has not been compacted or established as engineered fill; D is not made suitable merely by covering it with sand. Identifying the right type of bearing material does not establish its bearing capacity or determine the footing size.
Find it: Chapter 4 → Footings → general bearing requirements. Code section: 2024 IRC R403.1.
Correct answer: A. Undisturbed natural soil or compacted engineered fill
The footing must bear on undisturbed natural soil or compacted engineered fill. B leaves organic material in the bearing area; C has not been compacted or established as engineered fill; D is not made suitable merely by covering it with sand. Identifying the right type of bearing material does not establish its bearing capacity or determine the footing size.
Find it: Chapter 4 → Footings → general bearing requirements. Code section: 2024 IRC R403.1.
Question 6 of 30 · Footings and Foundations · 2024 IRC
A conventional exterior footing for a dwelling bears on soil. Frost protection does not require a greater depth, and no approved alternative foundation system applies. What is the general minimum depth below undisturbed ground level?
- A. 6 in
- B. 8 in
- C. 12 in
- D. 18 in
Show answer and explanation for Question 6 of 30
Correct answer: C. 12 in
Exterior footings must be at least 12 in below undisturbed ground level. A and B are too shallow; D is deeper than this general minimum, not the minimum itself. Frost protection can require a greater depth, which is why the question explicitly excludes that condition. Twelve inches is not a universal answer for every climate or foundation system.
Find it: Chapter 4 → Footings → depth and frost protection. Code section: 2024 IRC R403.1, footing-depth provisions.
Correct answer: C. 12 in
Exterior footings must be at least 12 in below undisturbed ground level. A and B are too shallow; D is deeper than this general minimum, not the minimum itself. Frost protection can require a greater depth, which is why the question explicitly excludes that condition. Twelve inches is not a universal answer for every climate or foundation system.
Find it: Chapter 4 → Footings → depth and frost protection. Code section: 2024 IRC R403.1, footing-depth provisions.
Question 7 of 30 · Footings and Foundations · 2024 IRC
The soil under a footing has been classified as silty sand (SM). Presumptive values are permitted, and no tested bearing-capacity value is available. Using the IRC's presumptive load-bearing values table, what bearing value applies?
- A. 1,500 psf
- B. 2,000 psf
- C. 3,000 psf
- D. 4,000 psf
Show answer and explanation for Question 7 of 30
Correct answer: B. 2,000 psf
Silty sand sits in the row for sand, silty sand, clayey sand, silty gravel and clayey gravel, which carries 2,000 psf. A (1,500 psf) is the clay and silt row, C (3,000 psf) is sandy gravel and gravel, and D (4,000 psf) is sedimentary and foliated rock. One related rule worth tabbing: where questionable soils are likely, the building official can require a soil test instead of relying on the table.
Find it: Chapter 4 → General → soil tests / presumptive load-bearing values table. Code section: 2024 IRC R401.4.1; Table R401.4.1(1).
Correct answer: B. 2,000 psf
Silty sand sits in the row for sand, silty sand, clayey sand, silty gravel and clayey gravel, which carries 2,000 psf. A (1,500 psf) is the clay and silt row, C (3,000 psf) is sandy gravel and gravel, and D (4,000 psf) is sedimentary and foliated rock. One related rule worth tabbing: where questionable soils are likely, the building official can require a soil test instead of relying on the table.
Find it: Chapter 4 → General → soil tests / presumptive load-bearing values table. Code section: 2024 IRC R401.4.1; Table R401.4.1(1).
Question 8 of 30 · Footings and Foundations · 2024 IRC
A sill plate is anchored to a concrete foundation using the ordinary prescriptive anchor-bolt method, without a more stringent wind or seismic fastening requirement. Which observation violates the general diameter, embedment or spacing limits?
- A. The bolts are 1/2 in in diameter
- B. The bolts are embedded 7 in
- C. The bolts are spaced 6 ft on center
- D. The bolts are spaced 7 ft on center
Show answer and explanation for Question 8 of 30
Correct answer: D. The bolts are spaced 7 ft on center
Anchor bolts can't be spaced more than 6 ft on center. A 1/2-in diameter and 7-in embedment meet the general minimums, and C is at the spacing limit. D exceeds it by 1 ft. This question checks those three limits; it does not establish that every other anchorage detail complies.
Find it: Index → "Anchor bolts". Code section: 2024 IRC R403.1.6.
Correct answer: D. The bolts are spaced 7 ft on center
Anchor bolts can't be spaced more than 6 ft on center. A 1/2-in diameter and 7-in embedment meet the general minimums, and C is at the spacing limit. D exceeds it by 1 ft. This question checks those three limits; it does not establish that every other anchorage detail complies.
Find it: Index → "Anchor bolts". Code section: 2024 IRC R403.1.6.
Question 9 of 30 · Footings and Foundations · 2024 IRC
A concrete foundation wall supports a house with fiber-cement lap siding and no masonry veneer. What is the minimum height the wall must extend above the adjacent finished grade?
- A. 4 in
- B. 6 in
- C. 8 in
- D. 12 in
Show answer and explanation for Question 9 of 30
Correct answer: B. 6 in
For the foundation wall described, the minimum extension above finished grade is 6 in. A is below that minimum. C and D are greater heights, not the minimum requested. This checks the foundation-wall height; it is not a substitute for checking the siding's separate installation requirements.
Find it: Chapter 4 → Foundation walls → height above finished grade. Code section: 2024 IRC R404.1.6.
Correct answer: B. 6 in
For the foundation wall described, the minimum extension above finished grade is 6 in. A is below that minimum. C and D are greater heights, not the minimum requested. This checks the foundation-wall height; it is not a substitute for checking the siding's separate installation requirements.
Find it: Chapter 4 → Foundation walls → height above finished grade. Code section: 2024 IRC R404.1.6.
Question 10 of 30 · Footings and Foundations · 2024 IRC
Vegetation and other organic material remain on the ground beneath a new crawl space. What does the IRC site-preparation requirement call for?
- A. Remove the vegetation and organic material
- B. Leave it in place if a vapor retarder covers it
- C. Compact the vegetation into the soil
- D. Leave it in place if the crawl space is ventilated
Show answer and explanation for Question 10 of 30
Correct answer: A. Remove the vegetation and organic material
The ground must be cleared of vegetation and organic material. Covering it, compacting it, or ventilating the space does not perform that removal. B and D confuse separate moisture-control measures with site preparation; C leaves the material the rule says to remove.
Find it: Chapter 4 → Under-floor space → removal of debris and organic material. Code section: 2024 IRC R408.5.
Correct answer: A. Remove the vegetation and organic material
The ground must be cleared of vegetation and organic material. Covering it, compacting it, or ventilating the space does not perform that removal. B and D confuse separate moisture-control measures with site preparation; C leaves the material the rule says to remove.
Find it: Chapter 4 → Under-floor space → removal of debris and organic material. Code section: 2024 IRC R408.5.
Floor Construction
Question 11 of 30 · Floor Construction · 2024 IRC
Compacted soil fill—not clean sand or gravel—is being placed below a concrete floor slab within the foundation walls. The building official has not approved a greater depth. What is the general maximum thickness of this fill?
- A. 2 in
- B. 4 in
- C. 8 in
- D. 24 in
Show answer and explanation for Question 11 of 30
Correct answer: C. 8 in
The general limit for compacted soil fill below the slab is 8 in unless otherwise approved. A and B are smaller thicknesses, not the maximum. D is the separate 24-in limit for clean sand or gravel. Read the material description before choosing the number; both limits appear in the same site-preparation discussion.
Find it: Chapter 5 → Concrete floors on ground → site preparation. Code section: 2024 IRC R506.3.
Correct answer: C. 8 in
The general limit for compacted soil fill below the slab is 8 in unless otherwise approved. A and B are smaller thicknesses, not the maximum. D is the separate 24-in limit for clean sand or gravel. Read the material description before choosing the number; both limits appear in the same site-preparation discussion.
Find it: Chapter 5 → Concrete floors on ground → site preparation. Code section: 2024 IRC R506.3.
Question 12 of 30 · Floor Construction · 2021 IRC
A plumber wants to notch the top edge of a solid-sawn 2×10 floor joist (actual depth 9-1/4 in). The notch is not at the end of the joist and not in the middle third of the span. Its length also complies with the notch-length limit. What is the maximum notch depth?
- A. About 1.54 in
- B. About 2.31 in
- C. About 3.08 in
- D. About 4.63 in
Show answer and explanation for Question 12 of 30
Correct answer: A. About 1.54 in
A notch in a solid lumber joist can't be deeper than one-sixth of the member's depth: 9.25 ÷ 6 ≈ 1.54 in. B is one-fourth of the depth, which is the limit only for notches at the ends of the member. C is one-third of the depth, the limit for the diameter of a bored hole. D is half the depth, which isn't a limit for anything here.
Math: 9.25 in ÷ 6 = 1.541666… in ≈ 1.54 in
Find it: Index → "Notching" (joists, sawn lumber). Code section: 2021 IRC R502.8.1.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF p. 1, sawn-lumber text and Figure 1
Correct answer: A. About 1.54 in
A notch in a solid lumber joist can't be deeper than one-sixth of the member's depth: 9.25 ÷ 6 ≈ 1.54 in. B is one-fourth of the depth, which is the limit only for notches at the ends of the member. C is one-third of the depth, the limit for the diameter of a bored hole. D is half the depth, which isn't a limit for anything here.
Math: 9.25 in ÷ 6 = 1.541666… in ≈ 1.54 in
Find it: Index → "Notching" (joists, sawn lumber). Code section: 2021 IRC R502.8.1.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF p. 1, sawn-lumber text and Figure 1
Question 13 of 30 · Floor Construction · 2021 IRC
Which single bored hole in a solid-sawn 2×12 floor joist (actual depth 11-1/4 in) complies with the IRC's diameter and edge-clearance limits? The joist has no other holes or notches.
- A. A 3-1/2 in hole centered in the joist's depth
- B. A 4 in hole centered in the joist's depth
- C. A 3 in hole whose edge is 1-1/2 in from the bottom of the joist
- D. A 2 in hole whose edge is 1 in from the top of the joist
Show answer and explanation for Question 13 of 30
Correct answer: A. A 3-1/2 in hole centered in the joist's depth
A bored hole can't be larger than one-third of the depth (11.25 ÷ 3 = 3.75 in), and its edge must stay at least 2 in from the top and bottom of the joist. A 3-1/2 in hole centered in the depth leaves about 3.9 in above and below it, so A passes. B is too big. C and D are small enough but too close to an edge.
Math: 11.25 in ÷ 3 = 3.75 in max; (11.25 − 3.5) ÷ 2 = 3.875 in to each edge
Find it: Index → "Boring" or "Notching" → sawn-lumber joists. Code section: 2021 IRC R502.8.1.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF p. 1, sawn-lumber text and Figure 1
Correct answer: A. A 3-1/2 in hole centered in the joist's depth
A bored hole can't be larger than one-third of the depth (11.25 ÷ 3 = 3.75 in), and its edge must stay at least 2 in from the top and bottom of the joist. A 3-1/2 in hole centered in the depth leaves about 3.9 in above and below it, so A passes. B is too big. C and D are small enough but too close to an edge.
Math: 11.25 in ÷ 3 = 3.75 in max; (11.25 − 3.5) ÷ 2 = 3.875 in to each edge
Find it: Index → "Boring" or "Notching" → sawn-lumber joists. Code section: 2021 IRC R502.8.1.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF p. 1, sawn-lumber text and Figure 1
Question 14 of 30 · Floor Construction · 2021 IRC
A 1-in-deep notch has been cut into the bottom edge of a solid-sawn floor joist at midspan to clear a drain line. The joist is 2×10. No engineered repair or alternative design has been approved. What should the inspector conclude?
- A. It's acceptable because the notch is less than one-sixth of the joist's depth
- B. It's acceptable because bottom-edge notches have no limits
- C. It's not acceptable because notches aren't permitted in the middle third of the span
- D. It's acceptable if the notch is filled with construction adhesive
Show answer and explanation for Question 14 of 30
Correct answer: C. It's not acceptable because notches aren't permitted in the middle third of the span
Notch depth isn't the only limit. Notches in solid lumber joists aren't allowed anywhere in the middle third of the span. A applies the depth rule but ignores the location rule. B wrongly exempts the bottom edge. D has no basis in the code. Fixing this would take an approved repair, such as an engineered one.
Find it: Index → "Notching" → sawn-lumber joists. Code section: 2021 IRC R502.8.1.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF p. 1, sawn-lumber text and Figure 1
Correct answer: C. It's not acceptable because notches aren't permitted in the middle third of the span
Notch depth isn't the only limit. Notches in solid lumber joists aren't allowed anywhere in the middle third of the span. A applies the depth rule but ignores the location rule. B wrongly exempts the bottom edge. D has no basis in the code. Fixing this would take an approved repair, such as an engineered one.
Find it: Index → "Notching" → sawn-lumber joists. Code section: 2021 IRC R502.8.1.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF p. 1, sawn-lumber text and Figure 1
Wall Construction and Coverings
Question 15 of 30 · Wall Construction and Coverings · 2021 IRC
What is the maximum notch depth allowed in a single 2×4 stud (actual width 3-1/2 in) in an exterior bearing wall? No approved stud shoe or engineered alternative applies.
- A. 7/8 in
- B. 1-3/8 in
- C. 1-3/4 in
- D. 2-1/8 in
Show answer and explanation for Question 15 of 30
Correct answer: A. 7/8 in
Studs in exterior walls and bearing partitions can be notched to no more than 25% of their width: 3.5 × 0.25 = 0.875 in, or 7/8 in. B, C and D all exceed that limit. The separate 40% nonbearing-partition limit would be 1.4 in for this stud—not exactly the 1-3/8 in in B. Use the actual 3-1/2-in width, not the nominal 4-in size.
Math: 3.5 in × 0.25 = 0.875 in
Find it: Index → "Studs" (cutting, notching and boring). Code section: 2021 IRC R602.6.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF pp. 1–2, stud text and Figures 2–3
Correct answer: A. 7/8 in
Studs in exterior walls and bearing partitions can be notched to no more than 25% of their width: 3.5 × 0.25 = 0.875 in, or 7/8 in. B, C and D all exceed that limit. The separate 40% nonbearing-partition limit would be 1.4 in for this stud—not exactly the 1-3/8 in in B. Use the actual 3-1/2-in width, not the nominal 4-in size.
Math: 3.5 in × 0.25 = 0.875 in
Find it: Index → "Studs" (cutting, notching and boring). Code section: 2021 IRC R602.6.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF pp. 1–2, stud text and Figures 2–3
Question 16 of 30 · Wall Construction and Coverings · 2021 IRC
In an exterior bearing wall, what is the largest hole you can bore through a single (not doubled) 2×6 stud (actual width 5-1/2 in)? The hole is centered, is not at the same cross section as a notch, and no approved stud shoe or engineered alternative applies.
- A. About 1.4 in
- B. About 2.2 in
- C. About 3.3 in
- D. About 3.9 in
Show answer and explanation for Question 16 of 30
Correct answer: B. About 2.2 in
A single stud in an exterior or bearing wall can be bored to no more than 40% of its width: 5.5 × 0.40 = 2.2 in. The edge of the hole must also stay at least 5/8 in from the face of the stud. C is 60% of the width, which is allowed only when the stud is doubled and no more than two doubled studs in a row are bored. A is about 25% of the width, and D is about 70%; neither is a boring limit.
Math: 5.5 in × 0.40 = 2.2 in (60% = 3.3 in, doubled studs only)
Find it: Same lookup as the stud notching question. Code section: 2021 IRC R602.6.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF pp. 1–2, stud text and Figure 2
Correct answer: B. About 2.2 in
A single stud in an exterior or bearing wall can be bored to no more than 40% of its width: 5.5 × 0.40 = 2.2 in. The edge of the hole must also stay at least 5/8 in from the face of the stud. C is 60% of the width, which is allowed only when the stud is doubled and no more than two doubled studs in a row are bored. A is about 25% of the width, and D is about 70%; neither is a boring limit.
Math: 5.5 in × 0.40 = 2.2 in (60% = 3.3 in, doubled studs only)
Find it: Same lookup as the stud notching question. Code section: 2021 IRC R602.6.
Source: ICC CodeNotes: IRC Cutting, Drilling and Notching — PDF pp. 1–2, stud text and Figure 2
Question 17 of 30 · Wall Construction and Coverings · 2021 IRC
A duct installation removes more than 50% of the width of the top plate in a bearing wall. The wall does not have an entire side covered with wood structural panel sheathing, and no equivalent approved repair applies. Which prescriptive tie detail is required?
- A. Nothing, as long as the cut is less than 6 in long
- B. Doubling the studs on both sides of the cut
- C. A third top plate over the full length of the wall
- D. A galvanized metal tie at least 0.054 in thick and 1-1/2 in wide, extending at least 6 in past each side of the opening, with at least eight nails on each side; nails at least 0.148 in in diameter and 1-1/2 in long
Show answer and explanation for Question 17 of 30
Correct answer: D. A galvanized metal tie at least 0.054 in thick and 1-1/2 in wide, extending at least 6 in past each side of the opening, with at least eight nails on each side; nails at least 0.148 in in diameter and 1-1/2 in long
The code calls for a 0.054-in (16-gauge) galvanized metal tie at least 1-1/2 in wide, extending at least 6 in past each side of the opening and fastened with at least eight specified nails on each side—not eight total. Doubling studs (B) and adding a third plate (C) aren't the prescribed fix, and the short-cut exemption in A doesn't exist. The question excludes the exception for a wall with an entire side covered by wood structural panel sheathing.
Find it: Index → "Top plate" (drilling and notching). Code section: 2021 IRC R602.6.1.
Correct answer: D. A galvanized metal tie at least 0.054 in thick and 1-1/2 in wide, extending at least 6 in past each side of the opening, with at least eight nails on each side; nails at least 0.148 in in diameter and 1-1/2 in long
The code calls for a 0.054-in (16-gauge) galvanized metal tie at least 1-1/2 in wide, extending at least 6 in past each side of the opening and fastened with at least eight specified nails on each side—not eight total. Doubling studs (B) and adding a third plate (C) aren't the prescribed fix, and the short-cut exemption in A doesn't exist. The question excludes the exception for a wall with an entire side covered by wood structural panel sheathing.
Find it: Index → "Top plate" (drilling and notching). Code section: 2021 IRC R602.6.1.
Question 18 of 30 · Wall Construction and Coverings · 2021 IRC
An installer wants to bore an engineered-wood header using the percentage limits for ordinary solid-sawn studs. What should determine whether the proposed hole is permitted?
- A. Apply the solid-sawn stud limits to every engineered-wood product
- B. Use the manufacturer's permitted modifications or a design by a registered design professional for that member before cutting
- C. Allow any hole centered in the header
- D. Allow any hole smaller than 1 in
Show answer and explanation for Question 18 of 30
Correct answer: B. Use the manufacturer's permitted modifications or a design by a registered design professional for that member before cutting
Engineered-wood members are not interchangeable with solid-sawn studs. Their permitted modifications must come from the manufacturer's recommendations or a design for the member by a registered design professional. A applies rules for a different type of member; C and D invent universal exceptions. Determine that the hole is permitted before making it.
Find it: Chapter 5 → Cutting, drilling and notching → engineered wood products. Code section: 2021 IRC R502.8.2; engineered-wood modification principle.
Correct answer: B. Use the manufacturer's permitted modifications or a design by a registered design professional for that member before cutting
Engineered-wood members are not interchangeable with solid-sawn studs. Their permitted modifications must come from the manufacturer's recommendations or a design for the member by a registered design professional. A applies rules for a different type of member; C and D invent universal exceptions. Determine that the hole is permitted before making it.
Find it: Chapter 5 → Cutting, drilling and notching → engineered wood products. Code section: 2021 IRC R502.8.2; engineered-wood modification principle.
Question 19 of 30 · Wall Construction and Coverings · 2024 IRC
An attached garage shares a wall with the dwelling, with no habitable room above the garage. Under the prescriptive gypsum-board separation method—not an alternative assembly—what is the minimum gypsum-board thickness on the garage side of that wall?
- A. 1/4 in
- B. 1/2 in
- C. 3/4 in
- D. 1 in
Show answer and explanation for Question 19 of 30
Correct answer: B. 1/2 in
The garage side of the wall requires at least 1/2-in gypsum board under this separation method. A is too thin. C and D are thicker than the minimum; they are not the minimum asked for. Do not substitute the separate requirement for a ceiling beneath habitable rooms, which the question excludes. Wall separation does not waive the door-opening protection checked in Question 29.
Find it: Chapter 3 → Fire-resistant construction → dwelling-garage separation. Code section: 2024 IRC Table R302.6.
Correct answer: B. 1/2 in
The garage side of the wall requires at least 1/2-in gypsum board under this separation method. A is too thin. C and D are thicker than the minimum; they are not the minimum asked for. Do not substitute the separate requirement for a ceiling beneath habitable rooms, which the question excludes. Wall separation does not waive the door-opening protection checked in Question 29.
Find it: Chapter 3 → Fire-resistant construction → dwelling-garage separation. Code section: 2024 IRC Table R302.6.
Question 20 of 30 · Wall Construction and Coverings · 2024 IRC
Inside an ordinary shower compartment, the required nonabsorbent wall surface must extend to at least what height above the floor?
- A. 4 ft
- B. 6 ft
- C. 7 ft
- D. 8 ft
Show answer and explanation for Question 20 of 30
Correct answer: B. 6 ft
The nonabsorbent wall surface must extend at least 6 ft above the floor. A stops too low. C and D exceed the required minimum, so they are not the minimum asked for. This is a wall-surface requirement, not the minimum ceiling height.
Find it: Chapter 3 → Toilet, bath and shower spaces → finish materials. Code section: 2024 IRC R327.1.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 66 (PDF p. 8), Bathroom Requirements
Correct answer: B. 6 ft
The nonabsorbent wall surface must extend at least 6 ft above the floor. A stops too low. C and D exceed the required minimum, so they are not the minimum asked for. This is a wall-surface requirement, not the minimum ceiling height.
Find it: Chapter 3 → Toilet, bath and shower spaces → finish materials. Code section: 2024 IRC R327.1.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 66 (PDF p. 8), Bathroom Requirements
Roof/Ceiling Construction
Question 21 of 30 · Roof/Ceiling Construction · 2024 IRC
An attic in a building with combustible roof and ceiling construction has 400 sq ft of area and 5 ft of vertical height. No appliance requires a larger opening. What is the minimum size of the rough-framed ceiling access opening?
- A. 16 in × 24 in
- B. 18 in × 24 in
- C. 22 in × 30 in
- D. 30 in × 30 in
Show answer and explanation for Question 21 of 30
Correct answer: C. 22 in × 30 in
This attic exceeds the 30-sq-ft area threshold and has at least 30 in of vertical height, so the access opening must be at least 22 × 30 in. For a ceiling opening, at least 30 in of unobstructed headroom is required at some point above the access. A and B are too small. D is larger than the minimum, not a prohibited size.
Find it: Index → "Attic access". Code section: 2024 IRC R807.1.
Correct answer: C. 22 in × 30 in
This attic exceeds the 30-sq-ft area threshold and has at least 30 in of vertical height, so the access opening must be at least 22 × 30 in. For a ceiling opening, at least 30 in of unobstructed headroom is required at some point above the access. A and B are too small. D is larger than the minimum, not a prohibited size.
Find it: Index → "Attic access". Code section: 2024 IRC R807.1.
Question 22 of 30 · Roof/Ceiling Construction · 2024 IRC
A new bathroom has a uniform, flat finished ceiling. No sloped-ceiling or other exception applies. What is its minimum ceiling height?
- A. 6 ft 4 in
- B. 6 ft 8 in
- C. 6 ft 10 in
- D. 7 ft
Show answer and explanation for Question 22 of 30
Correct answer: B. 6 ft 8 in
The minimum bathroom ceiling height is 6 ft 8 in under the ordinary rule. A is too low; C and D are higher than the minimum. The 7-ft figure in D is the general minimum for habitable spaces and hallways, not the bathroom minimum asked for here.
Find it: Chapter 3 → Ceiling height → minimum height. Code section: 2024 IRC R313.1.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 65 (PDF p. 7), Ceiling Height
Correct answer: B. 6 ft 8 in
The minimum bathroom ceiling height is 6 ft 8 in under the ordinary rule. A is too low; C and D are higher than the minimum. The 7-ft figure in D is the general minimum for habitable spaces and hallways, not the bathroom minimum asked for here.
Find it: Chapter 3 → Ceiling height → minimum height. Code section: 2024 IRC R313.1.
Source: ICC: 2024 IRC Study Companion, sample — Printed p. 65 (PDF p. 7), Ceiling Height
Question 23 of 30 · Roof/Ceiling Construction · 2021 IRC
A new roof has a 3:12 slope. The installer will use the conventional felt-underlayment method, not an approved alternative membrane or system. Can asphalt shingles be installed under the 2021 IRC?
- A. No, because asphalt shingles require a slope of at least 4:12
- B. Yes, with the standard single layer of felt underlayment
- C. Yes, with the two-layer felt-underlayment method for slopes from 2:12 up to, but not including, 4:12
- D. Only if the roof slope is increased to 6:12
Show answer and explanation for Question 23 of 30
Correct answer: C. Yes, with the two-layer felt-underlayment method for slopes from 2:12 up to, but not including, 4:12
Asphalt shingles are allowed on slopes of 2:12 or more. At 3:12, the conventional felt method needs two layers because the slope is below 4:12. A treats 4:12 as the minimum slope; it's actually where the standard single-layer method starts. B skips the low-slope requirement. D invents a 6:12 minimum. The question excludes approved alternative underlayment systems rather than treating every membrane as conventional felt.
Find it: Chapter 9 → Requirements for roof coverings → asphalt shingles (slope and underlayment). Code section: 2021 IRC R905, asphalt-shingle slope and underlayment provisions.
Correct answer: C. Yes, with the two-layer felt-underlayment method for slopes from 2:12 up to, but not including, 4:12
Asphalt shingles are allowed on slopes of 2:12 or more. At 3:12, the conventional felt method needs two layers because the slope is below 4:12. A treats 4:12 as the minimum slope; it's actually where the standard single-layer method starts. B skips the low-slope requirement. D invents a 6:12 minimum. The question excludes approved alternative underlayment systems rather than treating every membrane as conventional felt.
Find it: Chapter 9 → Requirements for roof coverings → asphalt shingles (slope and underlayment). Code section: 2021 IRC R905, asphalt-shingle slope and underlayment provisions.
Question 24 of 30 · Roof/Ceiling Construction · 2024 IRC
A house already has two layers of asphalt shingles. Under the ordinary prescriptive roof-recover rule, a contractor wants to install a third layer directly over them—not a separate roof system. What applies?
- A. It's allowed if the new shingles are architectural grade
- B. It's allowed if the roof slope is at least 4:12
- C. It's not allowed, because a roof recover isn't permitted where the existing roof already has two or more applications of roof covering
- D. It's allowed with a structural engineer's letter
Show answer and explanation for Question 24 of 30
Correct answer: C. It's not allowed, because a roof recover isn't permitted where the existing roof already has two or more applications of roof covering
The reroofing rules don't allow this recover over two or more existing applications of roof covering, so adding the proposed third layer requires removing the existing covering first. Shingle grade and roof slope don't change that. An engineer's letter alone is not a listed exception to this prescriptive restriction.
Find it: Index → "Reroofing". Code section: 2024 IRC R908.3.1.1.
Source: City of Ankeny: Roof / Reroof, 2024 IRC — PDF p. 1, Roof Recover
Correct answer: C. It's not allowed, because a roof recover isn't permitted where the existing roof already has two or more applications of roof covering
The reroofing rules don't allow this recover over two or more existing applications of roof covering, so adding the proposed third layer requires removing the existing covering first. Shingle grade and roof slope don't change that. An engineer's letter alone is not a listed exception to this prescriptive restriction.
Find it: Index → "Reroofing". Code section: 2024 IRC R908.3.1.1.
Source: City of Ankeny: Roof / Reroof, 2024 IRC — PDF p. 1, Roof Recover
Public Safety and Special Construction
Question 25 of 30 · Public Safety and Special Construction · 2024 IRC
A second-floor bedroom window that is not a grade-floor opening opens to a clear width of 20 in and a clear height of 24 in. Does the window qualify as an emergency escape and rescue opening?
- A. Yes, because it meets both minimum dimensions
- B. Yes, because upper-floor openings have no area requirement
- C. No, because its net clear opening is about 3.3 sq ft, below the required 5.7 sq ft
- D. No, because the minimum width is 24 in
Show answer and explanation for Question 25 of 30
Correct answer: C. No, because its net clear opening is about 3.3 sq ft, below the required 5.7 sq ft
Meeting the 20-in width and 24-in height minimums at the same time only gives 480 sq in, or about 3.3 sq ft. This nongrade-floor emergency escape opening also needs at least 5.7 sq ft of net clear opening, so at least one dimension has to be bigger. A is the trap this question is built around. B ignores the area requirement; D swaps the width and height minimums.
Math: 20 in × 24 in = 480 sq in ÷ 144 = 3.33 sq ft < 5.7 sq ft
Find it: Index → "Emergency escape and rescue openings". Code section: 2024 IRC R319.2.1.
Source: Jefferson County: Emergency Escape & Rescue Openings — R319.2.1, Minimum size
Correct answer: C. No, because its net clear opening is about 3.3 sq ft, below the required 5.7 sq ft
Meeting the 20-in width and 24-in height minimums at the same time only gives 480 sq in, or about 3.3 sq ft. This nongrade-floor emergency escape opening also needs at least 5.7 sq ft of net clear opening, so at least one dimension has to be bigger. A is the trap this question is built around. B ignores the area requirement; D swaps the width and height minimums.
Math: 20 in × 24 in = 480 sq in ÷ 144 = 3.33 sq ft < 5.7 sq ft
Find it: Index → "Emergency escape and rescue openings". Code section: 2024 IRC R319.2.1.
Source: Jefferson County: Emergency Escape & Rescue Openings — R319.2.1, Minimum size
Question 26 of 30 · Public Safety and Special Construction · 2024 IRC
A conventional interior straight stair has finished riser heights of 8 in and finished tread depths of 10 in, with compliant nosings. No special-stair or existing-building exception applies. Which dimensional problem is present?
- A. Nothing; both dimensions comply
- B. The treads are less than the 11-in minimum
- C. Both the risers and the treads fail
- D. The risers exceed the 7-3/4 in maximum
Show answer and explanation for Question 26 of 30
Correct answer: D. The risers exceed the 7-3/4 in maximum
For this conventional stair, the maximum riser height is 7-3/4 in and the minimum tread depth is 10 in. The treads pass and the risers don't. A overlooks the excessive rise; B substitutes an 11-in tread minimum; C wrongly fails the treads as well as the risers.
Find it: Index → "Stairways" (riser height, tread depth). Code section: 2024 IRC R318, stairway dimensional provisions.
Correct answer: D. The risers exceed the 7-3/4 in maximum
For this conventional stair, the maximum riser height is 7-3/4 in and the minimum tread depth is 10 in. The treads pass and the risers don't. A overlooks the excessive rise; B substitutes an 11-in tread minimum; C wrongly fails the treads as well as the risers.
Find it: Index → "Stairways" (riser height, tread depth). Code section: 2024 IRC R318, stairway dimensional provisions.
Question 27 of 30 · Public Safety and Special Construction · 2024 IRC
A handrail on a conventional stair—not an alternating-tread device or ship ladder—is installed so its top is 33 in above the tread nosings, measured vertically. Does it comply?
- A. Yes, because the allowed range is 30 to 38 in
- B. Yes, because any height works if the handrail is graspable
- C. No, because handrails must be exactly 36 in high
- D. No, because handrail height must be between 34 and 38 in
Show answer and explanation for Question 27 of 30
Correct answer: D. No, because handrail height must be between 34 and 38 in
Handrail height is measured vertically from the sloped plane along the tread nosings and must be at least 34 in and no more than 38 in. At 33 in, this rail is an inch too low. A gives the wrong lower limit. Graspability (B) is a separate requirement; it doesn't substitute for height. C incorrectly turns the permitted range into one exact height.
Find it: Index → "Handrails". Code section: 2024 IRC R320.2.
Correct answer: D. No, because handrail height must be between 34 and 38 in
Handrail height is measured vertically from the sloped plane along the tread nosings and must be at least 34 in and no more than 38 in. At 33 in, this rail is an inch too low. A gives the wrong lower limit. Graspability (B) is a separate requirement; it doesn't substitute for height. C incorrectly turns the permitted range into one exact height.
Find it: Index → "Handrails". Code section: 2024 IRC R320.2.
Question 28 of 30 · Public Safety and Special Construction · 2024 IRC
A level deck's walking surface is 32 in above grade at every point within 36 in horizontally of its open edge. The builder proposes a 34-in-high guard with clear openings of 3-1/2 in between balusters. What is the problem?
- A. A guard is required, and it must be at least 36 in high
- B. There is no problem, because a guard isn't required below 36 in
- C. The baluster spacing fails the 4-in sphere rule
- D. Nothing; both the height and the spacing comply
Show answer and explanation for Question 28 of 30
Correct answer: A. A guard is required, and it must be at least 36 in high
Guards are required where a walking surface is more than 30 in above the floor or grade below, measured within 36 in horizontally of the edge, and the required guard on this level deck must be at least 36 in high. The 3-1/2 in openings pass (so C is wrong), because a 4-in sphere can't get through. B confuses the guard height with the height that triggers the requirement.
Find it: Index → "Guards". Code section: 2024 IRC R321.1.1–R321.1.3.
Source: Jefferson County: Guards — Where required, Height, and Opening limitations
Correct answer: A. A guard is required, and it must be at least 36 in high
Guards are required where a walking surface is more than 30 in above the floor or grade below, measured within 36 in horizontally of the edge, and the required guard on this level deck must be at least 36 in high. The 3-1/2 in openings pass (so C is wrong), because a 4-in sphere can't get through. B confuses the guard height with the height that triggers the requirement.
Find it: Index → "Guards". Code section: 2024 IRC R321.1.1–R321.1.3.
Source: Jefferson County: Guards — Where required, Height, and Opening limitations
Question 29 of 30 · Public Safety and Special Construction · 2024 IRC
Which door can be installed between an attached garage and the house, where it opens into a kitchen?
- A. An unrated 1-3/8 in hollow-core wood door
- B. An unrated 1-3/4 in hollow-core wood door with no closer
- C. Any door, because the garage wall has gypsum board
- D. A 1-3/8 in solid wood door equipped to be both self-latching and self-closing
Show answer and explanation for Question 29 of 30
Correct answer: D. A 1-3/8 in solid wood door equipped to be both self-latching and self-closing
A door between the garage and the dwelling must be a solid wood door or a solid or honeycomb-core steel door at least 1-3/8 in thick, or a 20-minute fire-rated door. It must also be self-latching and must be either self-closing or automatic-closing. D satisfies those stated door requirements. A and B specify unrated hollow-core wood, which does not meet the listed material or rating alternatives; B also lacks closing protection. Gypsum board on the wall (C) does not waive opening protection. Also note: no opening is allowed from a garage directly into a sleeping room.
Find it: Index → "Garages" → opening protection. Code section: 2024 IRC R302.5.1.
Source: Jefferson County: Garage / Carports — R302.5.1, Opening protection
Correct answer: D. A 1-3/8 in solid wood door equipped to be both self-latching and self-closing
A door between the garage and the dwelling must be a solid wood door or a solid or honeycomb-core steel door at least 1-3/8 in thick, or a 20-minute fire-rated door. It must also be self-latching and must be either self-closing or automatic-closing. D satisfies those stated door requirements. A and B specify unrated hollow-core wood, which does not meet the listed material or rating alternatives; B also lacks closing protection. Gypsum board on the wall (C) does not waive opening protection. Also note: no opening is allowed from a garage directly into a sleeping room.
Find it: Index → "Garages" → opening protection. Code section: 2024 IRC R302.5.1.
Source: Jefferson County: Garage / Carports — R302.5.1, Opening protection
Question 30 of 30 · Public Safety and Special Construction · 2024 IRC
In a new two-story house with a basement, where does the IRC NOT require a smoke alarm?
- A. In each sleeping room
- B. Outside each separate sleeping area, in the immediate vicinity of the bedrooms
- C. In the basement, even though it has no bedrooms
- D. Inside the attached garage
Show answer and explanation for Question 30 of 30
Correct answer: D. Inside the attached garage
Smoke alarms are required in each sleeping room, outside each separate sleeping area near the bedrooms, and on each additional story of the dwelling, including basements. Those requirements account for A, B and C; the attached garage in D is not a listed smoke-alarm location. These are not all of the 2024 installation-location conditions—use the full section when checking a particular floor plan.
Find it: Index → "Smoke alarms". Code section: 2024 IRC R310.3.
Source: Jefferson County: Smoke Alarms — R310.3, numbered location list
Correct answer: D. Inside the attached garage
Smoke alarms are required in each sleeping room, outside each separate sleeping area near the bedrooms, and on each additional story of the dwelling, including basements. Those requirements account for A, B and C; the attached garage in D is not a listed smoke-alarm location. These are not all of the 2024 installation-location conditions—use the full section when checking a particular floor plan.
Find it: Index → "Smoke alarms". Code section: 2024 IRC R310.3.
Source: Jefferson County: Smoke Alarms — R310.3, numbered location list
Check your results
Count how many you got right. Then look at which questions you missed, and at any you got right by guessing.
That number tells you how you did on these 30 questions. It isn't an ICC score and it doesn't predict whether you'll pass. ICC certification exams use a scaled passing score of 75, and ICC is clear that 75 is not a percentage. Exam versions are adjusted for difficulty, so the number of correct answers needed can differ from one version to the next. You cannot turn that scaled score into a fixed B1 pass mark of 45 out of 60.
Use the right edition for the item. Questions 12–18 and 23 use the 2021 IRC; the other 22 questions use the 2024 IRC. You can review the 8-question 2021 group or the 22-question 2024 group separately. Neither group represents a full exam or its weighting, and an answer's edition label does not claim that the other edition has a different rule.
The most useful thing to do with a miss is find the rule yourself, not memorize the answer letter. Use a quick log like this one:
| Question | Why I missed it | Where the rule is in my book | What I'll do next |
|---|---|---|---|
| e.g., 13 | Checked hole diameter but missed edge clearance | 2021 IRC R502.8.1 | Check both diameter and distance to each edge |
| Wrong rule / missed a condition / wrong table / math / slow lookup / guessed |
Common reasons for misses on this set:
- Missing the qualifier. "Minimum," "maximum," "except," and "not" change the answer. ICC's own exam-day advice singles these words out.
- Choosing the wrong material or condition. Soil fill versus clean sand or gravel (Question 11), bearing versus nonbearing studs (Questions 15–16), and an ordinary gypsum separation versus a different assembly (Question 19) change which rule you need.
- Meeting one requirement and stopping. A room that meets the 7-ft dimension can still fail on area (Question 3). A window that meets the width and height minimums can still fail on net clear area (Question 25).
- Slow lookups. If finding a rule took more than a minute or two, make a note of its location and practice the lookup again. Follow the reference-material rules below when preparing exam-day tabs.
To practice pacing, try the whole set in 60 minutes. That's two minutes per question, the same average pace as the real exam's 60 questions in 2 hours. This is an optional mixed-edition practice exercise, not a simulation of a single-edition exam.
Answer key
Show the answer key
| # | Answer | IRC edition | Topic |
|---|---|---|---|
| 1 | D | 2024 | Code Administration |
| 2 | A | 2024 | Code Administration |
| 3 | C | 2024 | Building Planning |
| 4 | C | 2024 | Building Planning |
| 5 | A | 2024 | Footings and Foundations |
| 6 | C | 2024 | Footings and Foundations |
| 7 | B | 2024 | Footings and Foundations |
| 8 | D | 2024 | Footings and Foundations |
| 9 | B | 2024 | Footings and Foundations |
| 10 | A | 2024 | Footings and Foundations |
| 11 | C | 2024 | Floor Construction |
| 12 | A | 2021 | Floor Construction |
| 13 | A | 2021 | Floor Construction |
| 14 | C | 2021 | Floor Construction |
| 15 | A | 2021 | Wall Construction and Coverings |
| 16 | B | 2021 | Wall Construction and Coverings |
| 17 | D | 2021 | Wall Construction and Coverings |
| 18 | B | 2021 | Wall Construction and Coverings |
| 19 | B | 2024 | Wall Construction and Coverings |
| 20 | B | 2024 | Wall Construction and Coverings |
| 21 | C | 2024 | Roof/Ceiling Construction |
| 22 | B | 2024 | Roof/Ceiling Construction |
| 23 | C | 2021 | Roof/Ceiling Construction |
| 24 | C | 2024 | Roof/Ceiling Construction |
| 25 | C | 2024 | Public Safety and Special Construction |
| 26 | D | 2024 | Public Safety and Special Construction |
| 27 | D | 2024 | Public Safety and Special Construction |
| 28 | A | 2024 | Public Safety and Special Construction |
| 29 | D | 2024 | Public Safety and Special Construction |
| 30 | D | 2024 | Public Safety and Special Construction |
| # | Answer | IRC edition | Topic |
|---|---|---|---|
| 1 | D | 2024 | Code Administration |
| 2 | A | 2024 | Code Administration |
| 3 | C | 2024 | Building Planning |
| 4 | C | 2024 | Building Planning |
| 5 | A | 2024 | Footings and Foundations |
| 6 | C | 2024 | Footings and Foundations |
| 7 | B | 2024 | Footings and Foundations |
| 8 | D | 2024 | Footings and Foundations |
| 9 | B | 2024 | Footings and Foundations |
| 10 | A | 2024 | Footings and Foundations |
| 11 | C | 2024 | Floor Construction |
| 12 | A | 2021 | Floor Construction |
| 13 | A | 2021 | Floor Construction |
| 14 | C | 2021 | Floor Construction |
| 15 | A | 2021 | Wall Construction and Coverings |
| 16 | B | 2021 | Wall Construction and Coverings |
| 17 | D | 2021 | Wall Construction and Coverings |
| 18 | B | 2021 | Wall Construction and Coverings |
| 19 | B | 2024 | Wall Construction and Coverings |
| 20 | B | 2024 | Wall Construction and Coverings |
| 21 | C | 2024 | Roof/Ceiling Construction |
| 22 | B | 2024 | Roof/Ceiling Construction |
| 23 | C | 2021 | Roof/Ceiling Construction |
| 24 | C | 2024 | Roof/Ceiling Construction |
| 25 | C | 2024 | Public Safety and Special Construction |
| 26 | D | 2024 | Public Safety and Special Construction |
| 27 | D | 2024 | Public Safety and Special Construction |
| 28 | A | 2024 | Public Safety and Special Construction |
| 29 | D | 2024 | Public Safety and Special Construction |
| 30 | D | 2024 | Public Safety and Special Construction |
2021 vs. 2024 IRC: Chapter 3 section numbers
The 2024 IRC reorganized Chapter 3. If your tabs, notes, or study material use one edition and your exam uses the other, this table shows where each Chapter 3 section moved. A new number doesn't mean the wording is unchanged, so read the section itself in your edition.
| Topic | 2021 IRC | 2024 IRC |
|---|---|---|
| Design criteria | R301 | R301 |
| Fire-resistant construction (including garage separation) | R302 | R302 |
| Light, ventilation and heating | R303 | R325 |
| Minimum room areas | R304 | R312 |
| Ceiling height | R305 | R313 |
| Sanitation | R306 | R326 |
| Toilet, bath and shower spaces | R307 | R327 |
| Glazing | R308 | R324 |
| Garages and carports | R309 | R317 |
| Emergency escape and rescue openings | R310 | R319 |
| Means of egress | R311 | R318 |
| Handrails | R311.7.8.1–R311.7.8.6 | R320 (its own section) |
| Guards and window fall protection | R312 | R321 |
| Automatic sprinkler systems (2021 title: Automatic Fire Sprinkler Systems) | R313 | R309 |
| Smoke alarms | R314 | R310 |
| Carbon monoxide alarms | R315 | R311 |
| Foam plastic | R316 | R303 |
| Protection of wood against decay | R317 | R304 |
| Protection against subterranean termites | R318 | R305 |
| Site address | R319 | R308 |
| Accessibility | R320 | R322 |
| Elevators and platform lifts | R321 | R323 |
| Flood-resistant construction | R322 | R306 |
| Storm shelters | R323 | R307 |
| Solar energy systems | R324 | R329 |
| Mezzanines | R325 | R314 |
| Habitable attics | R326 | R316 |
| Swimming pools, spas and hot tubs | R327 | R328 |
| Energy storage systems | R328 | R330 |
| Stationary engine generators | R329 | R331 |
| Stationary fuel cell power systems | R330 | R332 |
| Sleeping lofts | none | R315 (new) |
Chapter 1 also changed one title: R103 is "Department of Building Safety" in 2021 and "Code Compliance Agency" in 2024.
Built from ICC's 2021 IRC contents, printed p. xxi, and 2024 IRC relocation tables, printed pp. 14–15, and contents, printed pp. 18–19. This is a location guide, not a claim that the two editions have identical requirements.
How this practice set compares to the real B1 exam
| Row label | ICC B1 exam | This practice set |
|---|---|---|
| Questions | 60 (ICC exam listing) | 30 original questions |
| Time | 2 hours (ICC exam listing) | Untimed, or 60 minutes for pacing practice |
| Code edition | ICC lists B1 in the 2021 and 2024 editions (ICC national exam list, updated January 12, 2026) | 22 questions labeled 2024; 8 labeled 2021—not a complete test for either edition |
| Coverage | Use the content outline for the exact purchased exam in the ICC Exam Catalog | Seven study-topic groups; no claim of official weighting or complete blueprint coverage |
| Result | Scaled 75 is the national certification passing standard; passing candidates see "PASS" without a number (ICC Support) | Your count of correct answers on these questions only |
Other B1 facts worth knowing before test day
- Pick the edition carefully when you buy. ICC's purchase page asks you to confirm the code year and testing method, and exam purchases are final. A purchase is valid for 365 days. (ICC exam listing)
- Testing options. ICC's PRONTO page describes testing on the ProctorU platform with live remote proctoring and at Meazure Learning test centers. Check which method is offered for your exact B1 purchase rather than assuming every method listed elsewhere by ICC applies. (ICC PRONTO)
- Your reference book. Check the approved references and open-/closed-book designation for your exact exam in the ICC Exam Catalog. For exams that allow references, ICC's exam rules allow original binding, three-ring binders or stapling; notes must be in ink or highlighted, and tabs must be permanently attached. Unauthorized photocopies of copyrighted material and loose papers aren't allowed. This practice page is not a list of approved exam-room materials.
- Results. You see your result on the testing site right after you finish. If you don't pass, ICC provides a diagnostic report you can use to see which content areas to work on. (ICC: After the Exam)
- Retakes. For national certification exams, you get six attempts within six months. After the sixth attempt, you have to wait six months from your first attempt to register again; each attempt requires a new exam fee. (ICC exam rules)
- Whether you need B1 for a job. Check the requirements of the agency or employer you'd be inspecting for. This national-certification study resource does not determine your eligibility for a particular job or local authorization.
Sources and verification
Last verified: October 5, 2026. Checked on that date: the B1 question count, time, listed code editions, scoring explanation, general reference-material rules, retake rules, results and testing options on the linked ICC pages; the Chapter 3 location map in ICC's two tables of contents and relocation tables; and the selected source passages supporting each question in its labeled edition. The dynamic B1 catalog's full approved-reference list and domain weights are not reproduced here.
How we wrote these questions: each one is original and built around an IRC requirement or an application of one. The answers use the edition-specific ICC publications and selected building-department code excerpts linked beside the questions. A local handout supports only the cited model-code passage; its local policies are not rules for every jurisdiction. These are study questions, not a substitute for the adopted code in your jurisdiction, which may amend the model IRC.
This resource was developed with AI assistance. Source checking is not professional code-official review; no named professional review is claimed. How we create and check our resources.
By the Castleport Test Prep Editorial Team.
Castleport Test Prep is an independent exam prep publisher. We are not affiliated with, endorsed by, or approved by the International Code Council. Exam and code names are used only to identify the subjects covered, and trademarks belong to their respective owners. All practice questions on this page are original and are not ICC exam questions. Practice results don't guarantee certification, licensure, or employment.