100+ Free ICC Res Energy Practice Questions

Pass your ICC Residential Energy Inspector/Plans Examiner (Exam 79) exam on the first try — instant access, no signup required.

✓ No registration✓ No credit card✓ No hidden fees✓ Start practicing immediately

~65-75% Pass Rate

100+ Questions

100% Free

1 / 100

Question 1

Score: 0/0

Per IECC Table R402.1.2, Climate Zone 5 wood-frame walls have a prescriptive cavity R-value of R-20 OR equivalent of:

R-19 + R-3ci

R-30 cavity only

R-15 + R-1ci

R-13 + R-5ci

to track

Same family resources

Explore More ICC Certifications

Continue into nearby exams from the same family. Each card keeps practice questions, study guides, flashcards, videos, and articles in one place.

More From This Family

Videos and articles for deeper review.

VideoFREE ICC B1 Residential Building Inspector Exam Guide 2026 (2024 IRC, 60 Qs, Pass First Try)ArticleFREE ICC B1 Residential Building Inspector Exam Guide 2026 (2024 IRC, 60 Qs, Pass First Try)27 min read ArticleFREE ICC B2 Commercial Building Inspector Exam Guide 2026 (2024 IBC, 80 Qs, Pass First Try)15 min read ArticleFREE ICC E1 Residential Electrical Inspector Exam Guide 2026 (NEC 2020/2023, 60 Qs, Pass First Try)24 min read ArticleFREE ICC M2 Exam Guide 2026: Commercial Mechanical Inspector Study Plan9 min read

2026 Statistics

Key Facts: ICC Res Energy Exam

50 Qs

Exam Questions

Open-book IECC

2 hrs

Time Limit

2.4 min/question

Passing Score

Scaled score

$230-$290

Exam Fee

Member / nonmember

IECC 2021

Reference Code

Chapter 4 [RE]

3 ACH50

Air Leakage Limit

CZ 3-8 per R402.4.1.2

ICC Exam 79 has 50 multiple-choice questions with a 2-hour open-book time limit, requires a scaled score of 75 to pass, and costs $230 for ICC members or $290 for nonmembers. The exam is based on the 2021 IECC residential provisions (Chapter 4 [RE]) and tests building envelope, mechanical systems, service water heating, lighting, and existing-building provisions. Test through Pearson VUE in-person or ICC PRONTO remote proctoring 24/7. The exam combines with Exam 78 to earn the IECC/HERS Compliance Specialist designation.

Sample ICC Res Energy Practice Questions

Try these sample questions to test your ICC Res Energy exam readiness. Each question includes a detailed explanation. Start the interactive quiz above for the full 100+ question experience with AI tutoring.

1Which code is the primary reference for the ICC Exam 79 Residential Energy Inspector/Plans Examiner?

A.International Residential Code (IRC)

B.International Energy Conservation Code (IECC), Residential Provisions

C.International Mechanical Code (IMC)

D.ASHRAE 90.1

Explanation: Exam 79 is based on the Residential Provisions of the International Energy Conservation Code (IECC), specifically Chapter 4 [RE]. The exam references either the 2021 or 2024 edition depending on the current exam bulletin. The IRC contains energy provisions in Chapter 11 but Exam 79 uses the IECC directly. ASHRAE 90.1 applies to commercial buildings under the IECC commercial provisions.

2How many multiple-choice questions are on the ICC Exam 79?

A.40

B.50

C.60

D.80

Explanation: Exam 79 contains 50 multiple-choice questions with a 2-hour time limit. The exam is open book and administered through Pearson VUE or ICC PRONTO remote proctoring. A scaled score of 75 is required to pass. Test takers have approximately 2.4 minutes per question.

3Per IECC Section R402.1.2, what is the minimum prescriptive ceiling R-value for Climate Zones 4 through 8?

A.R-30

B.R-38

C.R-49

D.R-60

Explanation: Table R402.1.2 of the 2021 IECC requires R-49 ceiling insulation in Climate Zones 4 through 8. Climate Zones 1 and 2 require R-30, and Zone 3 requires R-38. The R-49 requirement applies whether the insulation is in an attic, vaulted ceiling, or above-grade roof assembly. Exam tip: Memorize the ceiling values for each climate zone — they appear repeatedly on Exam 79.

4Per IECC Table R402.1.2, what is the maximum allowable fenestration U-factor for vertical windows in Climate Zone 5?

A.0.27

B.0.30

C.0.32

D.0.40

Explanation: Table R402.1.2 of the 2021 IECC sets the maximum vertical fenestration U-factor at 0.30 for Climate Zones 3 through 8. Climate Zones 1 and 2 allow 0.40 and 0.40 respectively. A lower U-factor means better insulating performance. Note that skylight U-factor limits are different (0.55 in CZ 4-8) and are listed in the same table.

5Per IECC R402.4.1.2, what is the maximum allowable air leakage rate for a residential dwelling in Climate Zones 3 through 8?

A.3 air changes per hour at 50 pascals

B.5 air changes per hour at 50 pascals

C.7 air changes per hour at 50 pascals

D.0.35 air changes per hour natural

Explanation: Section R402.4.1.2 of the 2021 IECC limits whole-building air leakage to 3 ACH50 (air changes per hour at 50 pascals) in Climate Zones 3 through 8 and 5 ACH50 in Climate Zones 1 and 2. The test must be conducted with a blower door per RESNET/ICC 380 or ASTM E779/E1827. The test result is documented on the certificate posted near the electrical panel.

6Per IECC R403.3.5, what is the maximum allowable total duct leakage when ducts are located outside the building thermal envelope?

A.4 cfm per 100 square feet of conditioned floor area

B.6 cfm per 100 square feet of conditioned floor area

C.8 cfm per 100 square feet of conditioned floor area

D.12 cfm per 100 square feet of conditioned floor area

Explanation: Section R403.3.5 of the 2021 IECC requires post-construction duct leakage to be 4 cfm per 100 square feet of conditioned floor area or less when measured at 25 pascals (0.1 in. w.c.). A rough-in test allows 4 cfm/100 sf with air handler installed, or 3 cfm/100 sf without. Ducts located entirely inside the thermal envelope are exempt from testing under R403.3.6.

7Per IECC R403.3.1, supply ducts located in attics must be insulated to a minimum of:

A.R-4

B.R-6

C.R-8

D.R-11

Explanation: Section R403.3.1 of the 2021 IECC requires supply ducts located in attics to be insulated to a minimum of R-8. All other ducts located outside the building thermal envelope must be insulated to at least R-6. Ducts located entirely within the conditioned space (inside the thermal envelope) have no insulation requirement under this section.

8Per IECC R404.1, what minimum percentage of permanently installed lamps in lighting fixtures must be high-efficacy lamps?

A.50%

B.75%

C.90%

D.100%

Explanation: Section R404.1 of the 2021 IECC requires not less than 90% of permanently installed lighting fixtures contain only high-efficacy lamps (typically LEDs with an efficacy threshold tied to wattage). The 2009 IECC required only 50% and the 2012/2015 editions required 75%. Low-voltage lighting and fixtures regulated by appliance standards are excluded from this calculation.

9Per IECC R403.1.1, programmable thermostats serving forced-air furnaces must be capable of controlling:

A.At least 2 programmed temperature settings per day

B.At least 4 programmed temperature settings per day

C.Heating and cooling simultaneously

D.Humidity and CO2 levels

Explanation: Section R403.1.1 of the 2021 IECC requires programmable thermostats on forced-air furnaces to be capable of controlling the heating and cooling system on a daily schedule with at least two programmable setback periods per 24-hour cycle. The thermostat must maintain set points and provide manual override capability. Default setpoints in the off occupied position must be programmed to 70F or lower for heating and 78F or higher for cooling.

10Per IECC R402.4.1.1, the air barrier and insulation installation must be verified by:

A.Plan review only

B.Visual inspection at framing/insulation stages using the Table R402.4.1.1 air barrier checklist

C.Calibrated blower door testing only

D.Infrared imaging mandatory

Explanation: Section R402.4.1.1 of the 2021 IECC requires the air barrier and insulation installation to be field-verified against the checklist in Table R402.4.1.1. This includes verifying continuous air barrier alignment with insulation, sealed penetrations, sealed rim joists, and insulation grade installation. The visual inspection is separate from and required in addition to the R402.4.1.2 blower door air leakage test.

About the ICC Res Energy Exam

The ICC Residential Energy Inspector/Plans Examiner exam (Exam 79) certifies professionals to inspect and review plans for one- and two-family dwellings and townhomes for compliance with the International Energy Conservation Code (IECC) residential provisions. The open-book exam covers Chapter 4 [RE] of the IECC — building thermal envelope, mechanical systems, service water heating, lighting, and the air leakage testing requirements (ACH50) and duct testing protocols that drive modern energy code compliance. Combined with ICC Exam 78, Exam 79 earns the IECC/HERS Compliance Specialist designation, qualifying inspectors and plans examiners for code-enforcement roles in jurisdictions adopting the IECC.

Questions

50 scored questions

Time Limit

2 hours

Passing Score

Scaled 75

Exam Fee

$230 member / $290 nonmember (ICC (Pearson VUE / PRONTO))

ICC Res Energy Exam Content Outline

28%

General Plans and Inspection

Construction documents, R401.3 certificates, inspection sequence, and Table R402.4.1.1 air barrier checklist verification

46%

Building Envelope

R-values, U-factors, SHGC, air leakage at 3 ACH50 (CZ 3-8), continuous insulation, and fenestration labeling per NFRC

10%

Mechanical Systems

Duct insulation (R-8 attic supply), UL 181 sealing, 4 cfm/100sf leakage limit, thermostats, fan efficacy, and Manual J/S sizing

Service Water Heating

Pipe insulation R-3 on 3/4-inch+, recirculation controls, drain water heat recovery, and water heater UEF efficiency

Electrical Power and Lighting

R404.1 high-efficacy lamp requirement (90%), high-efficacy definition (lm/W thresholds), and electrical penetration sealing

16%

Alterations, Additions, and Change of Use

Existing buildings — repairs, replacements, exposed cavities (R503.1.1), historic exemptions, and additions (R502)

10%

Additional Efficiency and Compliance Paths

R407 efficiency packages (5 options, must meet 1), ERI compliance (R406), UA tradeoff (R402.1.5), and renewable energy credit

How to Pass the ICC Res Energy Exam

What You Need to Know

Passing score: Scaled 75
Exam length: 50 questions
Time limit: 2 hours
Exam fee: $230 member / $290 nonmember

Keys to Passing

Complete 500+ practice questions
Score 80%+ consistently before scheduling
Focus on highest-weighted sections
Use our AI tutor for tough concepts

ICC Res Energy Study Tips from Top Performers

1Tab IECC Table R402.1.2 first — memorize wall, ceiling, floor, and basement R-values for at least Climate Zones 4, 5, and 6 (the most common test focus). Then add CZ 3 and 7 to your tabs

2Master the air leakage and duct testing limits cold — 3 ACH50 for CZ 3-8 (5 ACH50 for CZ 1-2) at 50 Pa, and 4 cfm/100sf for total duct leakage at 25 Pa. These appear repeatedly across the envelope (46%) and mechanical (10%) sections

3Know R-8 attic supply duct, R-6 other unconditioned-space ducts, R-3 hot water pipes (3/4-inch and larger), R-10 slab edge — these specific R-values trip up unprepared candidates. Tab R403.3.1 and R403.5.3 in your codebook

4Understand the four compliance paths in R401.2 — prescriptive (R402-R404), UA alternative (R402.1.5), simulated performance (R405), and ERI (R406). For ERI, know the 2021 IECC Table R406.5 targets: 57 for CZ 3-4, 55 for CZ 5-7, 53 for CZ 8

5Drill Table R402.4.1.1 air barrier checklist — knee walls, rim joists, dropped ceilings, recessed lights, attic hatches, tub/shower walls, and garage common walls. The 'General Plans and Inspection' section (28%) draws heavily from this single table

Frequently Asked Questions

What does ICC Exam 79 cover, and which code is the reference?

Exam 79 covers the residential provisions of the International Energy Conservation Code (IECC), Chapter 4 [RE]. The current exam edition references the 2021 IECC (with some jurisdictions transitioning to the 2024 IECC). Topics include building thermal envelope (R402), mechanical systems and ducts (R403), service water heating (R403.5), lighting (R404), simulated performance and ERI compliance paths (R405-R407), and existing-building alterations (R501-R503). The exam is open book; bring your codebook with tabs and highlighting.

How much does ICC Exam 79 cost and how long is it?

ICC Exam 79 costs $230 for ICC members and $290 for nonmembers. The exam has 50 multiple-choice questions with a 2-hour time limit, giving you about 2.4 minutes per question. A scaled score of 75 is required to pass. The exam is computer-based and administered through Pearson VUE testing centers or via ICC PRONTO remote proctoring 24/7. Schedule and pay through the ICC website at iccsafe.org/credentialing.

What is the air leakage limit (ACH50) under the 2021 IECC?

Section R402.4.1.2 of the 2021 IECC limits whole-building air leakage to 3 ACH50 (air changes per hour at 50 pascals) in Climate Zones 3 through 8, and 5 ACH50 in Climate Zones 1 and 2. The blower door test is conducted per RESNET/ICC 380, ASTM E779, or ASTM E1827 by an approved third-party tester such as a HERS Rater. Results are documented on the R401.3 certificate posted at the electrical panel.

What is the IECC/HERS Compliance Specialist designation?

The IECC/HERS Compliance Specialist designation is earned by passing both ICC Exam 78 (Commercial Energy Inspector) and ICC Exam 79 (Residential Energy Inspector/Plans Examiner). This combination credential qualifies you to perform energy code inspections and plan reviews for residential and commercial buildings, making it valuable for jurisdictions adopting the IECC. The HERS Rater (RESNET) credential complements but is separate from this ICC designation.

Is ICC Exam 79 open book? What can I bring?

Yes, Exam 79 is open book. You may bring the IECC Residential Provisions codebook (check the exam bulletin for the required edition — 2021 IECC at most recent printing). Tabs, highlighting, and handwritten margin notes are permitted. Printed inserts, loose papers, or supplementary study guides are not permitted in the exam room. Practice locating R402 envelope values, R403 duct provisions, and Table R402.4.1.1 air barrier criteria quickly — open book only helps if you can find sections in under 60 seconds.

How should I prepare for ICC Exam 79?

Start by reading IECC Chapter 4 [RE] and Chapter 5 [RE] in full to understand the structure. Tab key tables: R402.1.2 (R-values by climate zone), R402.1.3 (U-factor alternative), R402.4.1.1 (air barrier checklist), R403.5.1 (pipe length limits), R406.5 (ERI targets). Drill climate zone values until automatic — Zone 5 wood-frame walls (R-20 or R-13+5ci), Zone 4-8 ceilings (R-49), CZ 3-8 air leakage (3 ACH50). Complete at least 3 timed 50-question mocks with your codebook before scheduling.

100+ Free ICC Res Energy Practice Questions

ICC Residential Energy Inspector/Plans Examiner (Exam 79)

Explore More ICC Certifications

ICC Residential Building Inspector (B1)

ICC Commercial Building Inspector

ICC Commercial Mechanical Inspector (M2)

ICC Commercial Plumbing Inspector (P2)

ICC Property Maintenance and Housing Inspector

ICC Residential Electrical Inspector (E1)