International Green Construction Code


In 2009, the International Code Council launched the development of a new International Green Construction Code (IgCC) initiative, sub-titled “Safe and Sustainable: By the Book,” committing to developing a model code focused on new and existing commercial buildings addressing green building design and performance. The initial project of drafting of the IgCC Public Version 1.0 was undertaken with the American Institute of Architects (AIA) and the ASTM International. Ultimately, the IgCC Public Version 1.0 added new partners ASHRAE, USGBC and IES with the inclusion of ASHRAE Standard 189.1 as an option for jurisdictional requirements.

International Green Construction Code

Read the synopsis for the IgCC Public Version 2.0

The IgCC is the first model code to include sustainability measures encompassing an entire project and its site – from design and construction to certificate of occupancy and beyond. This code is expected to make buildings more efficient; reduce waste; and have a positive impact on health, safety, and community welfare. The IgCC is also concerned with air and indoor environmental quality.

In July 2016, ICC and ASHRAE announced their intent to consolidate the IgCC and ANSI/ASHRAE/ICC/IES/USGBC Standard 189.1, Standard for the Design of High-Performance, Green Buildings Except Low-Rise Residential Buildings. The scheduled publication date for this code is 2018.

Watch video explanations of the IgCC here or here.

Intent and Scope
  • Consistent and coordinated with the ICC family of codes and standards
  • Intended to be enforced primarily by building officials
  • Intended to drive green building into everyday practice
  • Applicable to the construction of all buildings, old and new, except IRC buildings, R-3 occupancies, and R-2 or R-4 occupancies that are four stories or fewer in height. Exceptions above are regulated by the ICC-700 National Green Building Standard where the jurisdiction indicates so in Table 302.1.
Chapter Details

Chapters 1 and 2 – Administration and Definitions
Like the other I-codes, the IgCC consists of minimum mandatory requirements and is intended to be adopted as such. The code is not a rating system and contains a new regulatory framework that facilitates jurisdictional customization.

Chapter 3 – Jurisdictional Requirement and Life Cycle Assessment (LCA)
Jurisdictional requirements allow the customization of the code to address 20 additional environmental criteria, giving local legislatures leeway to choose requirements that are appropriate and beneficial for their communities. This requirement also allows for jurisdictions to set higher minimum levels of performance. The whole building life cycle assessment is not a mandatory requirement. Instead, it is an alternative to the material selection requirement of Section 505.

Chapter 4 – Site Development and Land Use
Section 402 of the IgCC, pertaining to the preservation of natural resources, allows jurisdictions to prohibit construction in floodplains and limit the development of certain sites and site features. The registered design professional in charge of the project is required to submit an inventory and assessment of the natural resources and baseline conditions of the building site. The design and development of buildings and associated site improvements has to comply with the site design, water management, vegetation management, soil management, and waste management requirements in Chapter 4.

Chapter 5 – Material Resource Conservation and Efficiency
At least 50% of construction waste must be diverted, although jurisdictions can select a higher value in Table 302.1. There are also requirements for recycling areas used by building occupants. At least 55% of material must be recycled, recyclable, bio-based, or indigenous; materials are permitted to have multiple attributes. The code specifies mercury limits for fluorescent lighting and parameters for moisture control.

Chapter 6 – Energy Conservation, Efficiency, and Carbon Emission Reduction
This chapter is applicable to both new and existing buildings; it contains detailed energy requirements, including:

  • Modeled performance path requirements
  • Energy metering, monitoring, and reporting
  • Automated demand-response infrastructure
  • Building envelope systems
  • Building mechanical systems
  • Building service water heating systems
  • Building electrical power and lighting systems
  • Specific appliances and equipment
  • Building renewable energy systems
  • Energy systems commissioning and completion

The energy requirements for alterations to existing buildings can be found in Chapter 10.

The IgCC provides the following energy compliance paths: prescriptive-based and performance-based Zero Energy Performance Index (zEPI).

Chapter 7 – Water Conservation and Efficiency

  • Seeks water efficiency regardless of the source
  • Encourages the use of lower quality water wherever possible and permissible
  • Efficiency provisions for…
    • Plumbing fixtures and fittings
    • Appliances
    • Car washes
    • Cooling towers
  • HVAC systems and equipment water treatment systems metering
  • Rainwater collection systems
  • Gray water reuse systems
  • Reclaimed water systems
  • Other alternative water systems

Chapter 8 – Indoor Environmental Quality and Comfort

  • Indoor air quality management plan required
  • HVAC and air-handling systems
    • Air-handling system access
    • Durability and clean-ability
    • Filters
    • Ventilation requirements
  • Prohibits smoking in buildings
  • IAQ construction phase requirements
  • IAQ and pollutant control measures
  • Material emission limits
  • Acoustics (tied to T302.1)
  • Daylighting

Chapter 9 – Commissioning, Operations, and Maintenance

  • Pre-occupancy inspection and testing
  • Operation and maintenance manual
  • Building maintenance schedules
  • Address many issues beyond energy
  • Commissioning (T903.1)
    • List of items for which commissioning is required or encouraged
    • Distinguishes between pre-occupancy and post-occupancy commissioning

Chapter 10 – Existing Buildings

  • Alterations/renovations
    • Loosely based on IBC Chapter 34
    • Whatever is changed must meet current IgCC requirements
    • Unaltered components can remain as they are
    • Requirements are primarily related to energy and water
    • Capped at 10% of the total cost of alterations and other exceptions
  • Additions are treated much like new construction
  • Historic buildings are exempted from many provisions
  • Jurisdictions can choose to offer the evaluation of existing buildings for IgCC compliance
  • Chapter 11 covers similar information for building sites

Appendix A: Project Electives

  • Encourages and recognizes constructions that exceeds minimum code requirements
  • Encourages green practices that are difficult or impossible to mandate (e.g. infill and brownfield site development)
  • Encourages the implementation of practices that are not triggered by the code or mandated by the jurisdiction in Table 302.1
  • Enforceable only when specifically adopted
  • The jurisdiction sets the minimum number of electives that must be complied with on all projects constructed in the jurisdiction
  • The owner or the owners representative select the specific project electives to be implemented on each project