International Building Code (IBC)
Building codes are regulations that set out the standards to which buildings and other structures must conform. The International Building Code (IBC) is one of the codes established in the US by the International Code Council (ICC) and is applied by most of the country’s jurisdictions as well as internationally, although it can be amended to reflect local conditions and legislation.
IBC can be applied to most types of new buildings and is intended to ensure efficient and flexible building designs that protect health and safety and encourage the use of technological advances.
It requires that buildings and structures are classified under two categories:
- Use and occupancy.
- Type of construction.
Under use and occupancy there are several groups and subgroups that define a building’s specific use and are numbered based on the perceived risk the building poses to its occupants (the lower the number, the higher the risk). They are defined as follows:
| OCCUPANCY GROUP | SUBGROUPS | USES |
| Assembly |
A-1 (theatres, halls for performing arts) A-2 (restaurants) A-3 (worship and other recreation) A-4 (indoor arena) A-5 (stadiums) |
Places used for people gathering. |
| Business | B | Places used for providing services (e.g. banks, government buildings, police stations, offices). |
| Educational | E | Schools and day care centres. |
| Factory | F1 and F2 | Places used for manufacturing, packaging, repairing, etc. |
| High Hazard | H-1, H-2, H-3, H-4, and H-5 | Places involving hazardous materials (production, storage, etc.). |
| Institutional | I-1, I-2, I-3, and I-4 | Places where people are unable to leave without assistance (e.g. hospitals, care homes, prisons), |
| Mercantile | M | Commercial (e.g. shops, department stores, etc.). |
| Residential | R-1, R-2, R-3, and R-4 | Places providing overnight accommodation (e.g. houses, hotels, apartments, hostels, etc.). |
| Storage | S-1 and S-2 | Places where things are stored (e.g. warehouses, car parks, garages, etc.). |
| Utility and miscellaneous | U | Accessory structures and others (e.g. towers, barns, cooling towers, stables, tanks, retaining walls, etc.). |
Buildings can also be classified as a mixed occupancy type if they are occupied by more than one group type, and the different parts must conform to the codes for those areas. For example, a shopping centre with an underground car park will need to conform to both Group M and Group S.
The type of construction identifies the type of materials utilised for constructing the building or structure and classifies the level of combustibility and fire resistance associated with its elements (including primary structural frame, exterior and interior load-bearing and non-load-bearing walls, floor and roof). These are categorised as follows:
- Types I and II: Building elements are made of noncombustible materials.
- Type III: Exterior walls are made of noncombustible materials, the interior elements are made of any permissible material.
- Type IV: Exterior walls are made of noncombustible materials, interior elements are made of, or incorporate, timber.
- Type V: Structural elements comprise any permissible materials (A: Fire-resistance rated construction. B: Non fire-resistance rated construction).
[edit] Related articles on Designing Buildings Wiki
- Building codes.
- Building inspector.
- Building official.
- Building regulations.
- Code of practice.
- Design review.
- Certificate of occupancy.
- International Code Council ICC.
- International Existing Building Code (IEBC).
- International Residential Code (IRC).
- International Zoning Code (IZC).
- Licensed contractors in the USA.
- Performance specification.
- Planning permission.
- Office of Construction Services.
- Structural engineering codes.
- The role of codes, standards and approvals in delivering fire safety.
- What approvals are needed before construction begins.
- Zoning in the United States.
Featured articles and news
RTPI leader to become new CIOB Chief Executive Officer
Dr Victoria Hills MRTPI, FICE to take over after Caroline Gumble’s departure.
Social and affordable housing, a long term plan for delivery
The “Delivering a Decade of Renewal for Social and Affordable Housing” strategy sets out future path.
A change to adoptive architecture
Effects of global weather warming on architectural detailing, material choice and human interaction.
The proposed publicly owned and backed subsidiary of Homes England, to facilitate new homes.
How big is the problem and what can we do to mitigate the effects?
Overheating guidance and tools for building designers
A number of cool guides to help with the heat.
The UK's Modern Industrial Strategy: A 10 year plan
Previous consultation criticism, current key elements and general support with some persisting reservations.
Building Safety Regulator reforms
New roles, new staff and a new fast track service pave the way for a single construction regulator.
Architectural Technologist CPDs and Communications
CIAT CPD… and how you can do it!
Cooling centres and cool spaces
Managing extreme heat in cities by directing the public to places for heat stress relief and water sources.
Winter gardens: A brief history and warm variations
Extending the season with glass in different forms and terms.
Restoring Great Yarmouth's Winter Gardens
Transforming one of the least sustainable constructions imaginable.
Construction Skills Mission Board launch sector drive
Newly formed government and industry collaboration set strategy for recruiting an additional 100,000 construction workers a year.
New Architects Code comes into effect in September 2025
ARB Architects Code of Conduct and Practice available with ongoing consultation regarding guidance.
Welsh Skills Body (Medr) launches ambitious plan
The new skills body brings together funding and regulation of tertiary education and research for the devolved nation.
Paul Gandy FCIOB announced as next CIOB President
Former Tilbury Douglas CEO takes helm.
UK Infrastructure: A 10 Year Strategy. In brief with reactions
With the National Infrastructure and Service Transformation Authority (NISTA).