A building code is a set of rules that specify the minimum standards for constructed objects such as buildings and non-building structures. The main purpose of building codes are to protect public health, safety and general welfare as they relate to the construction and occupancy of buildings and structures. The building code becomes law of a particular jurisdiction when formally enacted by the appropriate governmental or private authority.
Building codes are generally intended to be applied by architects, engineers, constructors and regulators but are also used for various purposes by safety inspectors, environmental scientists, real estate developers, subcontractors, manufacturers of building products and materials, insurance companies, facility managers, tenants, and others. Codes regulating the design and construction of structures were adopted into law. Codes in developed western nations can be quite complex and exhaustive. They began in ancient times and have been developing ever since. Other codes may include fire, health, transportation, manufacturing, and other regulations/regulators/testers such as UL; Underwriters Labs. In essence they are minimum standards of design and implementation. Designers use ICC/IRC standards out of substantial reference books during design. Building departments review plans submitted to them before construction, issue permits and inspectors verify compliance to these standards at the site during construction.
There are often additional codes or sections of the same building code that have more specific requirements that apply to dwellings or places of business and special construction objects such as canopies, signs, pedestrian walkways, parking lots, and radio and television antennas.
Building codes have a long history. The earliest known written building code is included in the Code of Hammurabi which dates from circa 1772 BC.
The practice of developing, approving, and enforcing building codes varies considerably among nations. In some countries building codes are developed by the government agencies or quasi-governmental standard organizations and then enforced across the country by the central government. Such codes are known as the national codes (in a sense they enjoy a mandatory nation-wide application).
In other countries, where the power of regulating construction and fire safety is vested in local authorities, a system of model building codes is used. Model building codes have no legal status unless adopted or adapted by an authority having jurisdiction. The developers of model codes urge public authorities to reference model codes in their laws, ordinances, regulations, and administrative orders. When referenced in any of these legal instruments, a particular model code becomes law. This practice is known as adoption by reference. When an adopting authority decides to delete, add, or revise any portions of the model code adopted, it is usually required by the model code developer to follow a formal adoption procedure in which those modifications can be documented for legal purposes.
In Europe, the Eurocode is a pan-European building code that has superseded the older national building codes. Each country now has “country annexes” to localize the contents of the Eurocode.
Similarly, in India, each municipality and urban development authority has its own building code, which is mandatory for all construction within their jurisdiction. All these local building codes are variants of a National Building Code, which serves as model code proving guidelines for regulating building construction activity.
These requirements are usually a combination of prescriptive requirements that spell out exactly how something is to be done, and performance requirements which just outline what the required level of performance is and leave it up to the designer how this is achieved. Historically, the requirements are reactive; when a problem occurs, the building codes change to lessen the chance that the problem ever reoccurs. In recent years there has been a move amongst many building codes to move to more performance requirements and fewer prescriptive requirements.
Traditionally, building codes were short, simple interrelated sets of rules. They generally included references to hundreds of other codes, standards and guidelines that specify the details of the component or system design, specify testing requirements for components, or outline good engineering practice. These detailed codes required a great deal of specialization to interpret and also greatly constrained change and innovation in building design. In recent years, several countries, beginning with Australia, have moved to much shorter objective-based building codes. Rather than prescribing specific details, objective codes list a series of objectives all buildings must meet, while leaving open how these objectives will be met. When applying for a building permit, the designers must demonstrate how they meet each objective.
The National building code of Nigeria was promulgated in 2006 – an important contribution in the Nigerian building industry