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For residential building inspectors taking the ICC B1 exam

ICC B1 residential building inspector exam prep, free to start

Open book, 2 minutes a question. Find it in your IRC.

ICC B1 practice questions written to the 2024 IRC. Every answer is explained and your weakest area is named.

Free 10-question check

Full courses from $99, with lessons, timed practice exams and a study plan. See the courses →

Not sure? Compare the 3 exams.

  • No signup · No card
  • Every answer explained
  • Score by domain
  • Written to each exam's published outline
Ask Plumb AI Explains your misses, answers from this course, and builds practice from your weak spots.Try it free: 3 asks on the free check, 10 more with your email. What Plumb can do
ICC B1 free checkExample report
Code Administration78%
Building Planning52%
Footings and Foundations66%
Floor Construction40%
Study first: Floor Construction

Illustration of the breakdown you get at the end. These are not real scores.

Pick your exam

One free check for each exam

Original practice questions written to International Code Council's published outline. Every answer comes with a full explanation.

Each check is weighted to that exam's published content outline, so your score breakdown matches what you will be tested on. Each card has its exam's full course and price: lessons, timed exams and a study plan, with Plumb, your AI study assistant, built in.

Every course includes

  • Today's 10 with spaced review
  • Week-by-week plan to your exam date
  • Readiness by domain
  • Flashcards from your misses
  • Listen mode
  • Practice on your slowest questions
  • Exam-week mode
  • Your progress on any device
  • Lifetime access

Plumb, your AI study assistant, comes with every course: a week-by-week plan from your exam date and weak areas, step-by-step walk-throughs and a weak-spot quiz. Up to 40 messages a day.

More free practice

The Rafter Tie app

Study for the ICC B1, ICC B2 and ICC R3 exams anywhere you are

The Rafter Tie app for iPhone and Android is built around your study buddy, with quick practice questions and your study plan. Rafter Tie already works in your phone's browser today.

  • Today's questions, aimed at your weakest domain
  • Your week's plan, counting down to exam day
  • The same original questions and explanations as the site
  • Every exam on the site: ICC B1, ICC B2 and ICC R3
  • Plumb (AI), your Rafter Tie study buddy, explains why the answer is right and the others are not: 3 free asks, 10 more with your email

Plumb AI, your Rafter Tie study buddy, is at the center of the app.

  • Tutor walkthroughs: Step-by-step help on any question you answered, at your pace.
  • My study plan: A day-by-day plan built from your weakest domains.
  • Weak-spot quiz: Quiz yourself on what you missed, with spaced review so it sticks.
Get notified when it's ready

The International Code Council's Residential Building Inspector certification (exam B1) is one of the most common first credentials for building inspectors, and many jurisdictions require it or accept it. The exam is open book: you bring the International Residential Code (IRC) and look things up. With 60 questions in 2 hours, that leaves about 2 minutes a question, so finding it fast matters as much as knowing the code. Rafter Tie trains exactly that: find the section, read the conditions, answer. The course is written for the 2024 IRC, so check which code edition your exam uses before you buy.

What the B1 covers

The content outline has seven areas. Wall construction and coverings is the largest at 27%. Then come public safety and special construction (17%), footings and foundations (16%), floor construction (14%), roof and ceiling construction (14%), building planning (8%) and code administration (4%). Read the B1 exam outline guide.

New to inspecting? Read how to become a building inspector for the route in order, then check building inspector certification by state for your jurisdiction's rules.

References you can bring

The B1 is open book. These are ICC's rules as we read them; confirm them with ICC before you book.

  • Code book: The International Residential Code (IRC) for the edition you book. ICC lists the B1 on the 2021 and 2024 editions. ICC says hardcopy books are allowed, and any copyrighted, bound book may be used at a test site.
  • Open book: Yes. You may look things up in the IRC during the exam.
  • Tabs: Allowed if they are permanently attached, meaning a tab cannot be removed without destroying the page. Notes must be written in ink or highlighted, in a bound reference.
  • Not allowed: Photocopies of copyrighted material and loose papers.

Set up your book with our IRC tab list.

The exam in brief

  • Format: 60 multiple-choice questions, 2 hours, open book. The whole route is in ICC B1 certification: exam, cost and steps.
  • Where you test: through ICC's PRONTO system, at a test center, or online with a remote proctor where ICC's exam catalog lists remote delivery for your exam.
  • Online: study online, and sit the exam from home if your exam's catalog listing offers remote delivery; see what you can and cannot do online.
  • Cost: $320 per attempt at ICC's list price (members may pay less), and each retake is a new attempt.
  • Code book: ICC offers the exam on the 2021 and 2024 codes. Pick one edition and study with that book.

How to use Rafter Tie

  1. Take the free 10-question check, weighted to the seven content areas, with no signup. Every question is explained as you answer it.
  2. Tab your own IRC by chapter and by the topics you look up most, and practice finding sections against a timer.
  3. Spend extra time on wall construction, the biggest area, and on whichever area your free check shows is weakest.

Take the free 10-question check and see your score by outline area in minutes. The Rafter Tie course adds timed practice exams, a lesson for each outline area and a study plan built from your exam date.

Also on Rafter Tie: B2 and R3

Guides and tools

What do you need to work on?

All guides →

Exam facts and requirements

49 resources

What is on the exam, who can sit it, what it costs and how to keep it.

All 49 in exam facts and requirements →

Study guides

4 resources

Work through one topic at a time, with the method and worked examples.

All 4 in study guides →

Practice tests and drills

3 resources

Check yourself on questions, symbols and code look-ups, then see what to fix.

Tools and calculators

7 resources

Run the math your exam asks for and get the answer in seconds.

All 7 in tools and calculators →

Updated 10 November 2026.