The International Code Council’s (ICC’s) 2024 plumbing and mechanical codes have the most significant changes in 25 years. Photo courtesy International Code Council.

The 2024 editions of the International Code Council’s (ICC’s) International Plumbing Code (IPC) and International Mechanical Code (IMC) will provide the most substantial format changes to the International Codes (I-Codes) in 25 years.

ICC - Figure 1
Photo The Construction Specifier

The 2024 IPC and IMC will be the first codes among the 2024 I-Codes to undergo substantial formatting changes to improve the user experience and better align print and PDF versions of the I-Codes with the council’s digital codes content. These enhancements were developed and implemented based on feedback from print and digital I-Codes users and aim to improve readability.

Notable enhancements to the latest codes include additions such as QR codes, next to the revised codes for easy reference, and a pilot program of a Near Field Communication (NFC) tag to enhance user access to I-Codes support, increase security, and improve the product owner registration process.

The 2024 IPC improves public health through enhanced waste management requirements and plumbing system resilience to natural hazards. It also advances community sustainability through new water conservation measures, while assuring building accessibility through the integration of the updated ICC A117.1 Accessibility Standard, making the IPC the most comprehensive plumbing code available.

ICC - Figure 2
Photo The Construction Specifier

Some of the updates to the 2024 IPC include:

Provisions added for the support of buried piping beneath buildings where expansive soil conditions exist. Option added for vacuum testing of Drain Waste Vent (DWV) piping. Showerhead flow limited to 7.5 L [2.0 gallons per minute (gpm)], with performance complying with high efficiency requirements. Standards added for chemical waste piping and fitting materials.

The 2024 IMC establishes minimum regulations for mechanical systems using prescriptive and performance-related provisions. Important changes from the 2021 IMC to the 2024 IMC include:

Requirements prohibiting the use of domestic ductless range hoods in Groups I-1 and I-2 were removed. Group A2L and B2L refrigerant requirements have been added. Leak detection monitoring with alarm requirements have been added where the discharge from safety relief valves is not “readily visible” to occupants. Outside air requirements for dwelling units have increased. Requirements for exhaust system common ducts serving separate dwelling units have been added, requiring the common duct or shaft to be maintained at a negative pressure at all times.