The International Residential Code, abbreviated as the IRC, is one of the codes established in the US by the International Code Council.
It’s designed to safeguard the public health and safety of all in communities both large and small.
Here’s everything you should know about the International Residential Code.
1. What is the International Residential Code?
The International Residential Code is a “comprehensive, stand-alone residential code that establishes minimum regulations for one and two-family dwellings and townhouses using prescriptive provisions.”
The IRC is founded on broad-based principles that make both new materials and new building designs possible.
2. What are the benefits of the International Residential Code?
The International Residential Code contains a complete set of code provisions that covers all aspects of construction in a single source.
These factors include:
Building
Energy conservation
Plumbing
Mechanical
Fuel gas provisions included through an agreement with the American Gas Association
Electrical provisions from the 2017 National Electrical Code (NFPA 70)
3. What principles is the IRC based on?
The International Residential Code is based on the protection of public health, safety, and welfare.
The principles and the provisions in the code encourage the use of new and smarter technological advances.
It emphasizes prescriptive and engineered solutions that allow the use of time-tested methods.
4. What is today’s International Residential Code known for?
Today’s IRC is known for the following components:
Safety: The IRC provides prescriptive requirements for framing and foundations as well as a proven track record of providing safe, sanitary plumbing installations.
Convenience: The IRC utilizes an easy-to-use format.
New technology: The IRC embraces new technology. Both it and its predecessors have a tradition of innovation while protecting the health and safety of the public.
Correlation: The IRC is specifically correlated to work with the International Code Council’s (ICC) family of codes.
Transparency: The IRC has an open and honest code development process that is revised on a three-year cycle.
This process is modified on the International Code Council’s highly respected consensus code development procedure that draws upon the expertise of hundreds of plumbing, building and safety experts across North America.
5. Where is the International Residential Code used?
The International Residential Code (IRC) is in use or adopted in 49 states as well as the District of Columbia, Guam, Puerto Rico, and the U.S. Virgin Islands.
The IRC serves as a model code.
It is intended to be adopted in accordance with the laws and procedures of a governmental jurisdiction.
When adopting a model code, some jurisdictions amend the code in the process to reflect local practices and laws.
6. What does the IRC apply to?
The International Residential Code applies to new one and two-family dwellings and townhouses that are no taller than three stories.
It is intended to ensure efficient and flexible residential building designs that protect the health and safety of those living there as well as encourage the use of technological advances.
The IRC stipulates that anyone who intends to build, alter, repair, renovate, or demolish a building or structure to which the code applies must both apply for and obtain a required building permit.
7. What other types of building codes exist under the ICC?
If you’re currently investigating the International Residential Code, you may be interested in the other codes that the International Code Council has.
These include:
International Building Code (IBC)
International Residential Code (IRC)
International Fire Code (IRC)
International Plumbing Code (IPC)
International Mechanical Code (IMC)
International Fuel Gas Code (IFGC)
International Energy Conversation Code (IECC)
ICC Performance Code (ICCPC)
International Wildland Urban Interface Code (IWUIC)
International Existing Building Code (IEBC)
International Property Maintenance Code (IPMC)
International Private Sewage Disposal Code (IPSDC)
International Zoning Code (IZC)
International Green Construction Code (IGCC)
International Swimming Pool and Spa Code (ISPSC)
8. What’s the difference between the IRC and the IBC?
The International Residential Code and the International Building Code (IBC) are both parts of the International Code Council (IRC) .
It’s common to get these two codes confused, so you may hear people interchange the terms.
You may also hear people say that the International Building Code is the codebook for commercial construction while the International Residential Code is the codebook for residential construction.
This is not true.
We’ll look into the codebooks in this section to help you understand the differences between them.
The IRC has the following scope — one-and-two family dwellings and townhouses 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.
The following illustration from the Building Code Trainer can help you visualize what falls under the IRC’s provisions.
On the other hand, the International Building Code applies to every building, structure, or appurtenance except those structures covered by the International Residential Code.
Simply put, the IBC covers all types of buildings other than those buildings that are subject to the IRC.
For example, a detached residential 2-family dwelling is subject to the International Residential Code.
However, a detached residential 3-family dwelling is subject to the International Building Code.
Another good example is a townhouse that’s 3 stories above grade plane.
This townhouse would be subject to the provisions of the International Residential Code; however, a townhouse 4 stories above the grade plane is subject to the provisions of the International Building Code.
Note that you can be subject to the International Building Code if the project falls outside of International Residential Code provisions.
Likewise, if a building no longer conforms to the prescriptive provisions of the International Residential Code, then the structure must meet the provisions of the International Building Code.
9. What should you know about both the IBC and the IRC?
If you want to find reliable information about the International Building Code and International Residential Code, then you should look online through the International Code Council (ICC).
There are unofficial sources for both the IBC and the IRC.
However, you should only use them at your own risk.
The best place to look for any information relating to the International Residential Code is the International Code Council website.
Codes are updated every three years.
The IBC and IRC have been updated in 2000, 2003, 2006, 2009, 2012, 2015, 2018, and 2021.
The fixed schedule has prompted other organizations to align their publishing schedules with the IBC and IRC.
If you’ve performed work before a certain code was implemented, then it may be grandfathered in.
We recommend checking with your local permitting office to see if this is the case.
You can find a partial text of both the IBC and the IRC for free online through the International Code Council.
However, the council is known for strongly copyrighting its materials.
For example, it brought a 2016 lawsuit against the International Association of Plumbing and Mechanical Officials for alleged copying of intellectual property.
Municipalities can adopt model IBC and IRC codes to fit their local needs.
These are model codes that communities can adopt and adapt for their building needs.
They are not legal requirements on their own merits.
10. How do you obtain the official IRC?
If you’re a homeowner or building trade professional who does infrequent work, it’s probably not necessary for you to own a copy of the International Residential Code (or the International Building Code) as local code requirements will specify whatever IBC/IRC regulations will apply to construction.
That said, if you’re working with structures in a professional capacity, then you should consider becoming a member of the International Code Council.
Because it is an expenditure for your business, it’s likely to be tax-deductible while also giving you some key information to make sure you’re compliant.
Additionally, if you’re a serious “amateur” in the field and have a deep interest in building practices, then you may also find it useful to have access to a copy of the International Residential Code.
There’s an enormous amount of information in the code that you’ll find useful.
The best way to obtain an official International Residential Code is to join the International Code Council.
There are a handful of different membership options and some of these entitle you to a free copy of one of the international codes (in addition to other membership benefits).
If you don’t need the membership, then individual copies of the various codes are also available for sale.
These typically range in price from about $30 to $170 depending on whether you purchase a complete edition or an “essentials” edition.
Keep in mind that a membership may still be beneficial to you because members receive discounts on copies.
11. How much does the IRC cost?
Here are the prices for the full text of the International Residential Code from the International Code Council itself.
2021 IRC: $160 for nonmembers, $120 for members (softcover)
2018 IRC: $144 for nonmembers, $108 for members (softcover)
2015 IRC: $144 for nonmembers, $108 for members (softcover)
2012 IRC: $140 for nonmembers, $105 for members (softcover)
State codes are also available from the ICC starting at around $70.
It’s also worth noting that the International Code Council offers limited free access to lengthy portions of the International Residential Code in its public access section of the website.
If you’re seeking free information about the codes, this is a great place to start.
From there, you can decide whether or not it’s worthwhile to purchase.
Unofficial free access to the International Residential Code is also available.
However, in these cases, the code is not officially sanctioned, and there is no guarantee of its legitimacy.
Additionally, there may be issues with copyright infringement on these copies of the code.
12. Where can I look for free access to the codes?
Public Resource is a volunteer operation run by Carl Malamud out of San Francisco.
Malamud and a group of scanners believe that public information should be widely available and free to the public.
Archive.org is the host site for Public Resource activities.
This can be a good place to start if you want free access to the International Residential Code.
Note that, because the codes are copyrighted, they have been challenged by the organizations that own the copyrights.
Before you use any Archive.org documents, you should remember that all the files are maintained by volunteers only.
Final Thoughts
Use the information above to start your research on the International Residential Code!
Perhaps you came across the acronym while reading paperwork on your house that’s soon to be built or maybe you’re a contractor working in the field.
Either way, the above is useful information to have as the IRC serves as the base code standard for most jurisdictions in the United States.
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Disclaimer: we are not lawyers, accountants or financial advisors and the information in this article is for informational purposes only. This article is based on our own research and experience and we do our best to keep it accurate and up-to-date, but it may contain errors. Please be sure to consult a legal or financial professional before making any investment decisions.
Prior to starting Gokce Capital, Erika received a Bachelor of Architecture from the University of Southern California and a graduate degree in Urban Policy from Columbia University. She worked as both an architectural designer and engineer in New York before joining the New York City Department of Housing Preservation and Development.
Erika currently lives in the New York Metropolitan area with her spouse, daughter and cat. She is originally from Chicago and still considers herself a midwesterner at heart.
Erika also loves to read, write and travel (fun fact, she has visited all 50 states and more than 30 countries!). Her new book, Land Investing Mistakes: 11 True Stories You Need To Know Before Buying Land, is now available on Amazon.
Is there a website that gathers “public comments” for the International Code Council to consider when amending codes for 2024’s updated IRC?
Hello Terri, I’m actually not sure. I do know there are meetings where the public can comment (https://www.nahb.org/blog/2021/09/ICC-Public-Comment-Hearings-on-Proposed-Changes-to-Building-Codes-Begin-Sept-21), but I do not know if there is a way to leave a written comment.
Is there an opinion as to whether the IBC or IRC applies when a one family dwelling designed and used as a permanent home or residence has the use changed to transient as a short term rental ?
That’s a good question. I’m not sure if the code council has made a ruling on this, so it’s likely left up to local building code departments, but it sounds to me like a one-family short-term rental (if the owner isn’t occupying the building) should follow IBC standards: https://www.nfpa.org/News-and-Research/Publications-and-media/NFPA-Journal/2018/July-August-2018/Features/The-Airbnb-Challenge