International Existing Building Code (IEBC)
Building codes are regulations that set out the standards to which buildings and other structures must conform. The International Existing Building Code (IEBC) is a code established in the US by the International Code Council (ICC) and applied by most of the country’s jurisdictions as well as in some other countries internationally, (sometimes amended to reflect local conditions and legislation).
The sets out requirements for repairs, alterations and additions to existing buildings and structures. It applies to work on buildings and structures that were constructed before the introduction of the building code requirements in 2000.
In many cases, the cost of works that would be required to bring a building up to current compliance levels can be prohibitively high. The code provides three options that allow a controlled departure from full compliance with the codes dealing with new construction while at the same time maintaining basic standards for structural performance, fire prevention and other health and safety issues.
The main options provided by the code:
Option 1: Work shall be done in accordance with a Prescriptive Compliance Method. This follows provisions included in the IBC such as the following requirements:
- Existing materials shall be permitted to remain in use unless determined to be unsafe.
- New and replacement materials must conform to the applicable code for new construction.
- The building official has the authority to demand changes or works to be done to eliminate conditions that are deemed dangerous.
- Any additions must comply with the International Building Code (IBC) for new construction.
- Any alterations to the existing building must be such that the building as a whole is no less compliant with the IBC provisions that it was without the alterations.
- The building use or occupancy shall not be changed unless it is made to comply with the IBC.
- Historic buildings that are listed in the National Register of Historic Places do not need to be brought into compliance.
- Structures that are moved must comply with the IBC provisions for new structures.
Option 2: Work shall be done in accordance with a Work Area Compliance Method. This is the most flexible of the three options since specific code provisions are triggered only if the scale and level of work warrant them.
Option 3: Performance method. This is the least used of the three options. It provides the design team with a method of scoring the existing safety conditions of a building. Improvements must then be undertaken to improve the score to an acceptable level.
[edit] Related articles on Designing Buildings Wiki
- Alterations to existing buildings.
- Building codes.
- Building regulations.
- Change of use class.
- International building code (IBC).
- International Code Council ICC.
- International residential code (IRC).
- International Zoning Code (IZC).
- Permitted development.
- Renovation.
- Structural engineering codes.
- The role of codes, standards and approvals in delivering fire safety.
- What approvals are needed before construction begins.
Featured articles and news
Male construction workers and prostate cancer
CIOB and Prostate Cancer UK encourage awareness of prostate cancer risks, and what to do about it.
The changed R&D tax landscape for Architects
Specialist gives a recap on tax changes for Research and Development, via the ACA newsletter.
Structured product data as a competitive advantage
NBS explain why accessible product data that works across digital systems is key.
Welsh retrofit workforce assessment
Welsh Government report confirms Wales faces major electrical skills shortage, warns ECA.
A now architectural practice looks back at its concept project for a sustainable oceanic settlement 25 years on.
Copyright and Artificial Intelligence
Government report and back track on copyright opt out for AI training but no clear preferred alternative as yet.
Embedding AI tools into architectural education
Beyond the render: LMU share how student led research is shaping the future of visualisation workflows.
Why document control still fails UK construction projects
A Chartered Quantity Surveyor explains what needs to change and how.
Inspiration for a new 2026 wave of Irish construction professionals.
New planning reforms and Warm Homes Bill
Take centre stage at UK Construction Week London.
A brief run down of changes intentions from April in an onwards.
Reslating an ancient water mill
A rare opportunity to record, study and repair early vernacular roofs.
CIOB Apprentice of the Year 2025/26
Construction apprentice from Lincoln Mia Owen wins this years title.
Insulation solutions with less waste for a circular economy
Rob Firman, Technical and Specification Manager, Polyfoam XPS explains.
Recycled waste plastic in construction
Hierarchy, prevention to disposal, plastic types and approaches.
UK Net Zero Carbon Buildings Standard V1 published
Free-to-access technical standard to enable robust proof of a decarbonising built environment.





















