Codes & Climate Zones: What Fabricators Should Know
Understanding Green Building Codes in the U.S.
In the United States, green building strategies that can help reduce energy consumption are increasingly being introduced to traditional building codes. As a result, glass industry professionals must now be more mindful than ever of the environmental impact of their glass products.
There are two major building codes established in the U.S. that impact the glass industry: the International Energy Conservation Code® (IECC) and the American Society of Heating, Refrigeration & Air Conditioning code (ASHRAE). These codes are updated and adopted every three years to ensure design teams are employing energy efficient products in their projects.
Leading Code Organizations in the United States
The International Energy Conservation Code® (IECC) addresses energy efficiency on several fronts including cost, energy usage, use of natural resources and the impact of energy usage on the environment. It was most recently updated in 2021.
The American Society of Heating, Refrigeration & Air Conditioning (ASHRAE) is a member organization that advances the art and science of heating, ventilation, air conditioning, refrigeration and their allied fields with the vision of a healthy and sustainable built environment for all. In addition to its code, ASHRAE issues standardized maps of climate zones in North America and worldwide that help inform the necessary energy efficiency performance for various regions. It was most recently updated in 2021.
This climate zone map is provided by ASHRAE. Last update issued in 2021.
Code Adoption
States choose which version of each of these codes to adopt as the minimum requirements for construction in that state. Many projects choose to follow IECC, but frequently, projects pursuing specific green building certifications such as LEED® will choose to follow ASHRAE instead. Below is a timeline that combines code versions currently adopted by some states with approved model codes and codes in development from both IECC and ASHRAE:
Commercial code analysis map of adoption by state provided by the U.S. DOE Building Energy Codes Program (BECP). Last update issued 3/31/22. Please check the US DOE BECP website for the most up-to-date information.
Key Takeaways
For Vitro Certified™ fabricators, it is important to understand that codes are written for the entire window product including its framing, not just the glass that Vitro supplies. It is therefore difficult to provide specific recommendations of Vitro glass products that meet code requirements, but it is possible to make some assumptions about performance and convert from the code to determine which Vitro products would qualify when inserted into the window unit.
The information in this article about current green building code standards is intended to act as a good faith estimate of applicable codes and window performance. For the most up-to-date information on codes, consult with the U.S. Department of Energy (DOE) or your local code authority. For specific information about full window performance, consult with a window or curtainwall manufacturer or other qualified design professional.
