Illinois Codes FAQ

Does the Illinois Residential Building Code Act apply to repairs for existing construction?

No. It only applies to new residential construction. Residential repairs may be regulated by local Authorities Having Jurisdiction (AHJ). Contact the local AHJ (typically the municipality or county closest to the project site) for further guidance.

My roof was damaged in a storm and needs to be repaired. My insurance company wants to know if ice and water shield and drip edge are required by a building code. How should I answer that question?

The State has not adopted a building code for repairs to existing single family residences. However, both you and your insurance company should check with your unit of local government to verify if it has adopted any building code or ordinance regarding these. The unit of local government is usually either the city/village or county closest to the project site. If neither have adopted a code or ordinance addressing this, it is not required even though it is clearly good practice to do so. You should also verify if the roofing manufacturer requires these as a warranty condition.

Has the State of Illinois adopted a statewide building code for residential construction?

Yes, in general there are different requirements for jurisdictions that have adopted compliant building code(s) and those that are considered non-building code jurisdictions, but in either case the adopted code must meet the minimum structural requirements of the IRC.  Please see Building Codes and Regulations for specific requirements and editions.

Has the State of Illinois adopted a statewide building code for commercial construction?

Yes, in general there are different requirements for jurisdictions that have adopted compliant building code(s) and those that are considered non-building code jurisdictions, but in either case the adopted code must meet the minimum structural requirements of the IBC or IEBC.  Please see Building Codes and Regulations for specific requirements and editions.

Where can I find a list of building codes adopted by units of local government?

Local codes can be looked up using our online portal at Illinois Code Directory.  This directory identifies the adopted model code or codes, by title and edition, notes if any local amendments were adopted, and identifies the date when this information was reported to CDB.

I need help with the Illinois Plumbing Code.

The Plumbing Code is owned by the Illinois Department of Public Health and it regulates plumbers and the plumbing trade including licensure of plumbers and irrigation contractors. For all information related to the plumbing code, visit the IDPH Plumbing website.

Is there a statewide energy code?

Yes, the Illinois Energy Conservation Code (ILECC) applies to all buildings in the state.  If your municipality has adopted the ILECC, then you must abide by their inspection and enforcement requirements.  If your municipality has not adopted the ILECC, then you must still comply with the ILECC even though it may not be enforced.

Some municipalities have the authority to adopt more stringent energy codes which would be identified along with their other building codes.  For more information please see Illinois Energy Codes.

When do I have to meet the Illinois Stretch Energy Code?

The Stretch Energy Code only applies when it is adopted by the local municipality and can be adopted separately for residential or commercial construction.  When adopted by the local municipality, it replaces the Illinois Energy Conservation Code and becomes a mandatory requirement.  The Stretch Energy Code applies to all state funded buildings.  For more information please see Illinois Energy Codes.

Who is responsible for the interpretation and enforcement of the Illinois Energy Codes?

The Smart Energy Design Assistance Center (SEDAC) at the University of Illinois provides interpretations and technical assistance for the State Energy Codes.  Municipalities or counties that have adopted an energy code are responsible for enforcement.  CDB does not provide interpretations or enforcement except on projects it manages.

Where can I find information regarding the Illinois Accessibility Code?

For more information regarding the Illinois Accessibility Code, including Frequently Asked Questions, please visit our webpage: Illinois Accessibility Code.

I have a disagreement with the local code official. Can the State overrule the local code official’s decisions?

No. The local code official is the Authority Having Jurisdiction (AHJ) on privately funded projects. For projects involving state or federal facilities, please contact CDB for further guidance.

Can CDB provide building code interpretations?

CDB does not provide interpretations of building codes nor does CDB have the authority to overrule an Authority Having Jurisdiction (AHJ) on projects other than CDB projects. Contact the local AHJ (typically the municipality or county nearest the project site) for further guidance.

I am a renter. My landlord refuses to correct problems with my building. What can I do about this to force the landlord to make corrections?

Generally, building codes do not address conditions of existing buildings. However, if your unit of local government has adopted the International Property Maintenance Code, or an ordinance similar to this code, contact your local code official and ask for help resolving your issue. Also, consider notifying your city or county to ask for assistance. The State has no authority to intervene in such issues. Ultimately, resolution might require assistance from an attorney.

Does the State perform plan reviews, issue building permits, perform inspections for building code compliance or issue occupancy permits for privately funded construction?

No. If any of these are required, they would be addressed by the unit of local government.

My contractor’s work is poor quality and is not code compliant. What can I do?

Report the deficiencies to your local code official. If your unit of local government does not have a code official, consider seeking advice from a licensed architect, engineer, structural engineer, or legal advice from an attorney. The State has no authority to intervene in such cases.

Who should I contact regarding public schools?

Public School related projects are typically subject to the Health/Life Safety Code for Public Schools. The Illinois School State Board of Education is responsible for the administration and interpretation of that code and CDB is not able to provide further guidance. You would need to contact ISBE for code interpretations and enforcement. Typically the Regional Superintendent of Schools has the authority to provide guidance. ISBE also has a list of qualified plans examiners and inspectors that may be helpful.

• Illinois State Board of Education
  • Health and Life Safety
  • P: (217) 785-8779
  • E: ​hls@isbe.net

The local municipality and/or county has indicated that they do not issue building permits, provide inspection services, and/or enforce building codes for projects like mine; what should I do to comply with state statute?

The following may apply:

• Commercial projects will likely require a design professional licensed in the State of Illinois, such as an Architect, Structural Engineer, or Professional Engineer.
• Residential projects do not typically require a licensed design professional, but one may be utilized.
• See our website for a breakdown of typical codes that would likely apply to new and existing construction projects.
• A certification of inspection would likely be required per section 10.09 of the Capital Development Board Act.

What are the reporting requirements and how does a municipality/county report their building codes to the Capital Development Board?

In accordance with Section 10.18 of the Capital Development Board Act (20 ILCS 3105), all municipalities or counties adopting a new building code or amending an existing building code must provide, in writing, an identification of the code by title and edition, including local amendments, to the Capital Development Board at least 30 days before the effective date of the building code. Please be advised that the State of Illinois recently passed legislation (Public Act 103-0510) changing the Capital Development Board Act to require statewide baseline building codes effective 1/1/2025.  Locally adopted building codes must comply with the requirements of the Act.

The Capital Development Board has recently updated the software for our Illinois Municipal Code Directory. Please visit the new portal and confirm the code and contact information for your municipality. If there are discrepancies with the codes, please use the online County Municipal Code Reporting Form to notify CDB of your new or amended code. If you are a Code Official and need to update the contact information for a municipality, please send an email to cdb.buildingcodes@illinois.gov and someone will contact you with instructions. A walkthrough for this process is available upon request.

Does a municipality or county have to adopt building codes in order to comply with state statutes?

No. A municipality or county is not required to adopt building codes. If they do NOT adopt a building code then they are considered a non-building code jurisdiction and section 10.09-1 of the Capital Development Board Act (20 ILCS 3105) applies. If they do adopt a building code(s) then it must comply with section 10.18 of the Capital Development Board Act (20 ILCS 3105). See our website for major building codes that apply in non-building code jurisdictions.

Does a municipality/county have to adopt the International Building Code (IBC), International Existing Building Code (IEBC), and the International Residential Code (IRC)?

No, but any building codes adopted by a municipality must be based on model codes and must regulate the structural design of new commercial, existing commercial, and residential in a manner at least as stringent as the baseline building codes (IBC, IEBC, and IRC). The most common approach for fully complying with the CDB Act is to adopt the IBC, IEBC, and IRC and make local amendments as needed (as long as the amendments do not reduce the requirements for structural design).

Can a municipality/county adopt only a commercial code (i.e. the IBC)?

In order to comply with section 10.18 of the Capital Development Board Act (20 ILCS 3105) a municipality’s building code must regulate the structural design of new commercial, existing commercial, AND residential structures.

What happens if a municipality or county’s adopted code(s) does not comply with section 10.18 of the Capital Development Board Act?

If the adopted building code does not meet the requirements of section 10.18 then, then they are considered a non-building code jurisdiction and section 10.09-1 of the Capital Development Board Act (20 ILCS 3105) applies. See our website for major building codes that apply in non-building code jurisdictions.