IRC 2021 Building Code Explained
The IRC (International Residential Code) is the rulebook your city inspector uses to decide if your project passes. Here's what each chapter actually means — in plain English, organized by topic.
407 articles across 43 chapters
Scope and Administration
Chapter 1
Definitions
Chapter 2
Building Planning
Chapter 3
Foundations
Chapter 4
Floors
Chapter 5
Wall Construction
Chapter 6
Wall Covering
Chapter 7
Roof-Ceiling Construction
Chapter 8
Roof Assemblies
Chapter 9
Chimneys and Fireplaces
Chapter 10
Energy Efficiency
Chapter 11
Mechanical Administration
Chapter 12
General Mechanical System Requirements
Chapter 13
Heating and Cooling Equipment and Appliances
Chapter 14
Exhaust Systems
Chapter 15
Duct Systems
Chapter 16
Combustion Air
Chapter 17
Chimneys and Vents ? Mechanical
Chapter 18
Special Fuel-Burning Equipment
Chapter 19
Boilers and Water Heaters
Chapter 20
Hydronic Piping
Chapter 21
Special Piping and Storage Systems
Chapter 22
Solar Thermal Energy Systems
Chapter 23
Fuel Gas
Chapter 24
Plumbing Administration
Chapter 25
General Plumbing Requirements
Chapter 26
Plumbing Fixtures
Chapter 27
Water Heaters
Chapter 28
Water Supply and Distribution
Chapter 29
Sanitary Drainage
Chapter 30
Vents
Chapter 31
Vents
Chapter 31
Traps
Chapter 32
General Electrical Requirements
Chapter 34
Electrical Definitions
Chapter 35
Services
Chapter 36
Branch Circuit and Feeder Requirements
Chapter 37
Wiring Methods
Chapter 38
Power and Lighting Distribution
Chapter 39
Devices and Luminaires
Chapter 40
Appliance Installation
Chapter 41
Swimming Pools
Chapter 42
Class 2 Remote-Control, Signaling and Power-Limited Circuits
Chapter 43
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