The 2021 International Residential Code® (IRC®) Exam Study Course

internachi free international residential code irc exam study course

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That’s awesome,but, we are currently learning what the 2023 Code is all about.


Yes, but local building departments normally adopt these codes many years after they are released.


We have at least one AHJ here in my area still running the 2009 IRC. :crazy_face:


Please post the link to the 2023 IRC that you are currently learning, @sfetty.

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I apologize Ben for the misunderstanding, I’m currently studying the new 2023 Florida Building Code… Here’s the 2023 FBC Residential Which is based on the 2021 IRC. So this should be very helpful. Thanks for all you do.


In reference to Writing Assignment #1, 2021 IRC Exam Study Course:

In the section below, it reads the “specific requirement of this code” shall be applicable should there be a conflict between the specific and general requirements.

102.1 Code Conflicts

Where there is a conflict between a general requirement and a specific requirement of this code, the specific requirement shall be applicable. Where, in any specific case, different sections of the code specify different materials, methods of construction or other requirements, the most practical requirement to meet the intent of the code shall govern.


In reference to writing assignment #1 of the 2021 International Residential Code Exam Study Course:

The purpose of the International Residential Code is to regulate the broad spectrum of construction activities associated with residential buildings and structures(IRC R101.2). The scope of the IRC applies to detached one- and two-family dwellings and multiple single-family dwellings not more than three stories above grade plane in height with a separate means of egress and their accessory structures not more than three stories above grade plane in height(IRC R101.2).

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  • What is the purpose and scope of the International Residential Code? The IRC is used to regulate the construction activities that are associated with residential structures and buildings.
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  • What is the definition of light-framed construction? A system of light-gage steel or repetitive wood framing members that form the horizontal and vertical structural elements constitute light framed construction.
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  • Where natural light is used to satisfy the minimum illumination requirements, how is the minimum required amount of glazing determined? Where artificial light is used, what illumination level is mandated? The code is somewhat vague in the study companion. The study states that an 8 percent glazed area is required, however, it does not state if this is for lighting or ventilation. The book also states that “It has become increasingly more common to use artificial lighting and a mechanical ventilation system.”
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The scope and purpose of the IRC is:
The provisions of this code shall apply to the construction, alteration, relocation, enlargement, replacement, repair, equipment, use and occupancy, location, maintenance, removal and demolition of every building or structure or any appurtenances connected or attached to such buildings or structures. The purpose of this code is to establish the minimum requirements to provide a reasonable level of safety, health and general welfare through structural strength, means of egress, stability, sanitation, light and ventilation, energy conservation, and for providing a reasonable level of life safety and property protection from the hazards of fire, explosion or dangerous conditions, and to provide a reasonable level of safety to fire fighters and emergency responders during emergency operations.

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The definition of Light-Framed construction is: Construction whose vertical and horizontal structural elements are primarily formed by a system of repetitive wood or cold-formed steel framing members.

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What is the purpose and scope of the international residential code?

The IRC is intended to regulate the variety of topics related to the construction of residential zoned buildings and structures, to include the activities associated. Construction planning, building, and administration of activities associated, including all trades and related areas of focus, such as energy efficiency and existing structure modification.

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What is a dead load? Live load?

Dead load is the weight of all materials and affixed components of a structure that typically will remain static over time. Live load is the weight of additional components that are added to a structure after it is completed - such as vehicles, people, furniture, storage, etc.

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  • Where must illumination be located in relationship to interior stairways? Exterior stairways?

Illumination must be located in a manner to illuminate landings and treads. Lighting should not be less than one foot candle for each tread. Exterior stairwells require a light source at the top landing, considering basement stairwells - light source is required at the bottom landing.

  • How many egress doors from a dwelling are required? Under what conditions is an additional egress door required? What is the minimum required size of an egress door?

A minimum of one egress door is required from a dwelling. Increased occupant loads on a commercial building impacts the number and size of egress door requirements. The minimum required size is 32”x78” - hinged on the side.

  • How must lots be graded? What is the minimum required slope of the grade away from the foundation?

Lots must be graded to drain water away from the foundation. Minimum requirement is 6” within the first 10’.

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In reference to Writing Assignment #2, IRC Exam Study Course:

What is a live load? What is a dead load?
Dead load consists of permanent, static weights, while live load encompasses transient, variable loads.

R301.4 Dead load. The actual weights of materials and construction shall be used for determining dead load with consideration for the dead load of fixed service equipment.

R301.5 Live load. The minimum uniformly distributed live load shall be as provided in Table R301.5.

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What is the purpose and scope of the International Residential Code?

The International Residential Code (IRC) is a comprehensive set of building codes developed to regulate the construction of residential buildings. Its purpose is to ensure the safety, durability, and energy efficiency of residential structures. The IRC provides guidelines for various aspects of construction, including building materials, structural integrity, fire safety, plumbing, mechanical systems, and electrical systems. It aims to protect the health and welfare of the occupants by establishing minimum standards for residential construction.

The scope of the IRC covers one- and two-family dwellings, as well as townhouses that are three stories or less in height. It addresses both new construction and renovations, providing detailed requirements and specifications for different components of residential buildings. These codes are intended to be adopted and enforced by local governments to standardize residential construction practices and create safe living environments for residents.

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What is the definition of light-framed construction?

Light-framed construction refers to a construction method in which the primary structural elements are made of thin, light materials. Typically, this involves the use of wood or steel studs, joists, and rafters, which are assembled to create a framework for the building. This method is widely used in residential and commercial construction due to its cost-effectiveness and ease of construction. Light-framed construction allows for quick assembly and is often used for buildings where the loads are relatively light, such as houses and small to medium-sized commercial structures.

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What are the limitations for notches in floor joists? Bored holes?

Cuts, notches, and holes can’t be in the same location


Notches in solid lumber joists, rafters and beams shall not exceed one-sixth of the depth of the member, shall not be longer than one-third of the depth of the member and shall not be located in the middle one-third of the span. Notches at the ends of the member shall not exceed one-fourth the depth of the member.

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