- What the Credential Actually Is
- Who Issues It and How It Fits the ICC Family
- Exam Format and Question Style
- The Six Content Areas You Must Master
- The 2021 vs. 2024 Edition Question
- Fees, Registration and Purchase Rules
- Eligibility and What Is Not Verified
- Who Uses This Certification
- Keeping the Certification Current
- Sequencing Your Preparation
- Frequently Asked Questions
- REI-PE is the Residential Energy Inspector/Plans Examiner credential from the International Code Council, tied to ICC examination 79.
- The exam has 50 four-option multiple-choice questions, a two-hour limit, and a published price of US$320.
- You need a scaled score of 75, which is not necessarily 75% raw accuracy.
- Exam 79 is listed in 2021 and 2024 code editions, so buy and study for the matching one.
What the Credential Actually Is
Residential Energy Inspector/Plans Examiner (REI-PE) is a certification for professionals who review residential construction documents and inspect homes for compliance with the International Energy Conservation Code (IECC). A plans examiner reads drawings and energy documentation before construction and decides whether the design meets the code. An inspector verifies in the field that what was built matches what was approved: insulation levels, air sealing, window performance, duct work, lighting and the other provisions that govern how much energy a home uses.
The certification demonstrates that you can apply the residential energy code in both roles. It is a knowledge-based, code-focused credential, not a general green-building or home-performance designation. If you have seen other credentials that share the "REI-PE" letters in unrelated industries, they are entirely different; this site and this article concern only the ICC residential energy credential.
For additional background framed around the name and acronym itself, see our companion pieces on what REI-PE stands for and the REI-PE meaning.
Who Issues It and How It Fits the ICC Family
The International Code Council administers the certification. The supplied batch identifier "REI-PE" is a convenient label for this credential, but ICC's own catalog refers to it as examination 79, Residential Energy Inspector/Plans Examiner. When you search ICC's store or its national examination list, look for the full title and the exam number rather than the acronym.
ICC also offers a related combined IECC/HERS designation aimed at HERS Raters and Rating Field Inspectors. That path is separate from standalone exam 79. Being a HERS Rater is not established as a prerequisite for sitting the standalone residential energy inspector/plans examiner exam, and you should not assume the two credentials are interchangeable.
Exam Format and Question Style
The format is straightforward and consistent with how ICC runs its national examinations:
| Feature | What ICC Publishes |
|---|---|
| Number of questions | 50 |
| Time allowed | Two hours |
| Question type | Multiple choice, four options, one correct answer |
| Passing standard | Scaled score of 75 |
| Open book? | Yes, with published reference restrictions |
| Remote delivery | PRONTO remote-proctored delivery is verified |
Why the scaled score matters
ICC states that the passing score is a scaled score of 75, not necessarily 75% of questions answered correctly. Scaling accounts for differences in difficulty between exam forms, so the raw number of correct answers that converts to a scaled 75 can vary. Do not plan around "I can miss exactly 12 questions." Instead, aim for broad, confident coverage. Our REI-PE passing score guide explains the scaling concept in more detail.
Open book does not mean easy
An open-book exam rewards candidates who can locate provisions quickly. With 50 questions in two hours you have roughly two and a half minutes per item, which sounds generous until a question requires you to find a table, interpret footnotes and apply an exception. Candidates who tab and annotate their code book in advance, within the published rules for permitted references, tend to move faster. Review ICC's page on what to bring to the test site, and confirm the approved reference list for the exact edition you purchased. For a realistic view of difficulty, read how hard the REI-PE exam is.
The Six Content Areas You Must Master
ICC's published preparation curriculum for exam 79, built around the 2024 IECC, lists six topics. These are preparation-course topics, not a verified formal blueprint with official percentage weights, so treat them as a study map rather than a scoring formula. For a deeper walkthrough of each, see our complete guide to the six REI-PE content areas.
Domain 1: History and future of energy codes
Context for why the IECC looks the way it does and where it is heading.
- How successive code editions have changed stringency and structure
- The relationship between model code adoption and state or local amendments
- Why the edition you are tested on matters when questions reference specific requirements
Domain 2: Administration and documentation requirements
The process side of code enforcement, which is central to the plans examiner role.
- What construction documents must show to demonstrate compliance
- Required certificates, labels and inspection records
- How approvals, inspections and corrections flow through a jurisdiction
Domain 3: Compliance options
The IECC offers more than one route to compliance, and you must know which applies and what each demands.
- Prescriptive paths versus performance-based alternatives
- Tradeoffs and what documentation each path requires
- Recognizing when a project is using an option correctly
Domain 4: Specific thermal envelope and systems provisions
The technical core: insulation, fenestration, air leakage, ducts and building systems in residential construction.
- Reading the tables for insulation and fenestration requirements by climate zone
- Air barrier, air sealing and testing provisions
- Duct, mechanical, lighting and service water heating requirements
Domain 5: How the IECC relates to existing buildings
Energy code applies to more than new homes.
- Alterations, additions and repairs, and what triggers compliance
- Change of occupancy or use considerations
- Knowing which provisions apply to the altered portion versus the whole building
Domain 6: Expanded appendices of the 2024 IECC
Material beyond the main chapters that candidates sometimes overlook.
- Locate and understand the appendices as published in the 2024 edition
- Know how optional or supplemental provisions are adopted
The 2021 vs. 2024 Edition Question
ICC's national exam list shows exam 79 offered in both the 2021 and 2024 code editions. That creates a practical trap: the book you study from must be the book that matches the exam you purchase. A candidate who prepares from the 2024 IECC and then sits a 2021-edition exam, or the reverse, can lose points on questions where requirements differ between editions.
Before you pay, confirm which edition your jurisdiction expects and which edition your purchase specifies. ICC's preparation course for the 2024 residential provisions explicitly targets exam 79 using the 2024 IECC, while ICC's IECC/HERS page discusses reference materials in terms of the 2021 IECC. Neither edition should be silently substituted for the other. When approved references and study materials are tied to a specific edition, buy those, and do not mix them.
Key Takeaway
Pick your edition first, then buy the matching exam and reference book. Treat the edition as the first decision in your preparation plan, not an afterthought at checkout.
Fees, Registration and Purchase Rules
The current exam product on ICC's store displays US$320 for the examination. The store renders separate member and non-member price fields, but a verified member discount or complete member/non-member price pair could not be confirmed, so do not assume a discount exists. Check the live product page at checkout for your exact price.
- Use window: An examination purchase must be used within 365 days.
- Refunds: Purchases are non-refundable.
- Transfers: Purchases are non-transferable.
- Delivery: Remote proctoring through PRONTO is verified; no additional testing provider for exam 79 is asserted here.
The non-refundable, non-transferable terms mean you should not buy until you are reasonably ready to schedule. A 365-day window is generous, but it is not an invitation to purchase early and drift. For the complete picture including related costs, see our REI-PE certification cost breakdown. If scheduling is your concern, our exam dates and scheduling guide covers the practical side.
Eligibility and What Is Not Verified
No exam-79-specific education or experience minimum was verified in accessible ICC material. In other words, the published materials reviewed here do not establish a required degree, a required number of years in the field, or a prior license as a condition of sitting the exam. That is different from saying no requirements exist anywhere; your employer, state or local jurisdiction may impose its own expectations on who can perform plan review or inspections. Always confirm with the authority that will rely on your credential. Our REI-PE requirements guide goes deeper on this question.
What is also unverified
Two commonly asked questions do not have verified answers for this credential. First, there is no verified population pass rate. ICC's marketing language about course participants passing at high rates is a statement about a particular training population, not a pass rate for all candidates, which is why our REI-PE pass rate article treats the topic cautiously. Second, there is no exam-79-specific salary estimate or demonstrated earnings premium. Pay depends on employer type, region and role; see our REI-PE salary guide and the ROI analysis for how to think about value without relying on invented figures.
Who Uses This Certification
The credential is built around two job functions, and the people who benefit tend to cluster around them:
- Building departments and code officials: Plans examiners and inspectors who review residential permits for energy compliance.
- Third-party plan review and inspection firms: Companies that contract with jurisdictions or builders to perform compliance verification.
- HERS Raters and field inspectors: Energy-rating professionals who want to broaden into code compliance verification work. ICC and RESNET have promoted this crossover, though the combined IECC/HERS designation is a separate credential.
- Builders, energy consultants and contractors: Professionals who want to understand how reviewers think so their submissions pass the first time.
Because the credential signals competence in the energy chapters specifically, it tends to be most relevant where residential energy compliance is a distinct job function rather than a side duty. For a closer look at employment, see our page on REI-PE jobs.
Keeping the Certification Current
ICC certifications renew on a cycle, and the renewal fee is separate from the examination fee. Under the current ICC credentialing renewal bulletin, one certification has a three-year renewal cycle requiring 1.5 CEUs, including at least 0.8 qualifying Part 1 CEUs. The renewal fee shown is $105 for members and $130 for non-members.
The bulletin itself carries a source-version discrepancy: the parsed text indicates a July 28, 2026 date while the rendered cover shows January 6, 2026. The fee and CEU tables agree across both, but you should open the live bulletin and confirm the details that apply on the day you renew.
Key Takeaway
Start collecting qualifying CEUs early in your three-year cycle. Waiting until the final months, and needing to satisfy a specific Part 1 minimum, is how credentials lapse unnecessarily.
Sequencing Your Preparation
Because the exam is open book and code-driven, preparation is less about memorizing numbers and more about learning where things live and how provisions interact. Here is one way to sequence the six content areas, with the reasoning built in. For a fuller plan, use our REI-PE study guide and keep the one-page cheat sheet handy for last-minute review.
Orientation and compliance structure
- Cover history of energy codes and administration/documentation requirements first, since they frame everything else.
- Learn the compliance options so later technical sections make sense.
Thermal envelope and systems
- Spend the most time here; it is the technical heart of the exam and the area historically emphasized.
- Tab the tables and practice reading climate-zone requirements quickly.
Existing buildings and appendices
- Work through alterations, additions and the 2024 appendices.
- Run timed mixed practice questions to simulate two hours for 50 items.
When you are ready to test your recall under realistic conditions, take a few timed sessions on our REI-PE practice test and review every miss against the code book rather than just reading the explanation.
Frequently Asked Questions
It demonstrates knowledge of the residential energy provisions of the IECC for both plan review and field inspection. Whether it authorizes you to perform official duties depends on your employer and jurisdiction, so confirm with the authority that will rely on it.
The exam has 50 multiple-choice questions with four options each and one correct answer, delivered over two hours. Remote proctoring through PRONTO is verified for this exam.
Not exactly. ICC requires a scaled score of 75, which is not necessarily 75% raw accuracy. Because of scaling, you should aim for broad mastery rather than counting an allowable number of misses.
Exam 79 is listed in both the 2021 and 2024 editions. Study the edition that matches the exam you purchase and use the approved references for that same edition. Do not mix editions.
No. Exam purchases are non-refundable and non-transferable, and they must be used within 365 days. Buy only when you are ready to schedule.
Understanding what the certification covers, how the exam is structured and what rules govern purchase and renewal puts you in a position to prepare deliberately rather than guess. For additional definitions and background, you can also browse our overview pages on what REI-PE certification is and REI-PE training.