Housing Policy Explainer

How Building Codes Are Created

How are building codes created? Who writes these provisions? As housing policy reform moves beyond land use reforms, these questions are being asked more frequently throughout the country. Most states and communities do not write their building codes from scratch, instead relying on model building codes created by nonprofits and organizations whose primary or secondary focus is to create model building codes for governments to adopt.

While each code has its narrow focus and scope, its provisions are meant to provide a balance of occupant health and safety, durability of the structure, and affordability, along with other provisions unique to that code’s subject matter.

Model Code Process

Each code publisher follows its own process and timeline for code reviews yet there are several commonalities across the publishers. 

The next edition of any model building code begins with its current edition. Members of the organizations that publish these codes can propose a code change via written comments. At some point, these will become available for review by the members or the general public before the members vote on the proposal. Some codes, like the International Code Council’s I-Codes, undergo multiple rounds of voting and public hearings. After a final vote, the model codes are turned over to the editing team to work up the next version of the code to be published. Once complete, the model codes are available electronically and in hard copy form. 

With the exception of the U.S. Access Board and floodproofing regulations from the federal government, the model building codes and their processes are not government processes.

Model Codes and Their Publishers

Below is a list of select model building codes by publisher that are commonly used in the adoption of building codes. 

American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE):

  • Energy Standard for Sites and Buildings Except Low-Rise Residential Buildings

International Association of Plumbing and Mechanical Officials (IAPMO)

  • Uniform Plumbing Code
  • Uniform Mechanical Code

International Code Council (ICC):

  • International Building Code
  • International Energy Conservation Code
  • International Existing Building Code
  • International Fire Code
  • International Fuel Gas Code
  • International Mechanical Code
  • International Plumbing Code
  • International Residential Code

Note: These codes are often referred to as the “I-Codes”

National Fire Protection Association (NFPA):

  • National Electrical Code 
  • Fire Code
  • Standard for the Installation of Fire Sprinkler Systems

U.S. Access Board:

  • ADA Accessibility Standards 
Local Adoption

The model building codes are not laws, but rather a roadmap for policymakers to weigh the unique needs and legal requirements of the level of government adopting the codes. Local adoption of building codes happens at either the state, county, or city level. 

Local adoption is done through a process outlined at the level of adoption, with each level of adoption having to comply with all rules and regulations surrounding the adoption of laws. The model codes are used as the basis of these local codes and will be modified or amended as the promulgating level of government sees fit. Stakeholder engagement is key in local adoption, with building officials, builders, architects, subcontractors, and additional stakeholders providing input on the proposed codes. 

Following the adoption of new codes, builders, contractors, trade partners, architects, and code officials are trained on the new codes before they become effective. The timeline between adoption and effective data will vary by jurisdiction. 

Emergency updates are sometimes made at either the model code level or by local adoption, with new provisions added or current provisions suspended. This can be due to an urgent issue identified with the model code, a critical update due to life or safety concerns, or a lack of materials available that a given code requires.

Statewide Codes

In states with uniform, statewide building codes, there is a consistent set of requirements for the state, which may vary based on climactic conditions, location, and weather patterns. Local units of government cannot exceed these requirements with local amendments. Presently 10 states have uniform building codes: Connecticut, Florida, Kentucky, Massachusetts, Michigan, Minnesota, Montana, Ohio, Rhode Island, and Wisconsin. 

Local Codes

Sixteen states allow counties or cities to adopt their local building codes specific to that level of government. In these situations, a building’s cost and code requirements may vary from community to community. States with local code adoption include: Alabama, Alaska, Arizona, Colorado, Delaware, Illinois, Iowa, Kansas, Mississippi, Missouri, Nebraska, Nevada, South Dakota, Tennessee, Texas, and Wyoming.

Hybrid Adoption

Twenty-four states establish a baseline state building code and allow local governments (cities or counties) to make amendments within their jurisdiction. Codes will still vary across the state, but the state provides the minimum construction standard which cannot be lowered. These states include: Arkansas, California, Georgia, Hawaii, Idaho, Indiana, Louisiana, Maine, Maryland, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Oklahoma, Oregon, Pennsylvania, South Carolina, Utah, Vermont, Virginia, Washington, and West Virginia.

Building Codes and Housing Affordability 

By establishing the minimum construction standard in a jurisdiction, the codes have a direct impact on housing affordability. 

Over the years, building product manufacturers have found success in using both model codes and local code adoption as tools to increase sales and product use. Known as regulatory marketing, these firms use the building code to mandate their product. 

Since regulatory marketing exists at the model code level, in state and local code adoption, and in some cases local zoning codes, there is no single solution for this practice. The simplest solution is for the industry to voluntarily end the practice and focus on performance-based regulatory goals. As this is unlikely, options exist at various levels to address this affordability issue.

In recent years, policymakers have examined ways to place guardrails on local code adoption. In 2011, the state of Wisconsin enacted a law requiring any code changes costing more than $1,000 to go through the state legislature for final approval. Several states have passed a statewide ban on aesthesis mandates, which can overlap with building requirements covered by the state building code. Legislation directing specific building code changes has also grown popular, with single-stair, multifamily dwellings becoming a topic state legislatures are looking at following state and local land-use reforms.