CALGreen: An Introduction

CALGreen: An Introduction

By Shakari Mcgill

Sustainability is best defined as creating and maintaining the conditions under which humans and nature can exist in productive harmony to support present and future generations. As the population continues to grow, so does our need for new places to live, work, and play. Finding a balance between economic expansion and protecting our natural resources has breathed new life into many industries and their respective markets.

Not only has the architecture field seen a push to include measures and products that curtail energy use, water use, and waste creation; the construction industry has also seen their policies change to require more environmental consciousness. With the construction of a building accounting for 50- 60% of its lifetime energy use, it is paramount that enforceable, continuously-updated policies like the California Green Building Standards Code (CALGreen) exist to mediate this growth and ease stress that development can put on the environment.

CALGreen is part 11 of the California building energy efficiency standards known as Title 24. CALGreen’s base level mission attempts to dampen the environmental impact of construction through site slope preservation, drainage mitigation, and careful planning to mitigate any negative effects on neighboring areas. Compliance is two-tiered: To achieve CALGreen Tier 1, buildings must comply with the latest edition of “Savings By Design, Healthcare Modeling Procedures.” A second tier provides a higher degree of sustainability by requiring buildings to exceed the most current edition of “Savings by Design Modeling Procedures” by a measure of 15% of higher, according to the International Code Council.

CALGreen is not meant to be rigid and limiting; this type of policy is intended to be adaptive. It grows and changes in three-year intervals,  driven by responses to new research and industry, and is built incrementally upon previous improvements, allowing the market to catch up. Some changes CALGreen will see in 2019 are:

  • A new measure requiring all multifamily housing construction to comply with CALGreen (as compared to the previous iteration, which only requires compliance for building sites with 17 or more units).

In 2018, Verdical Group worked on a high-profile Tier 1 residential project; had this project been permitted in 2019, it would have seen elevated energy savings from the inclusion of a DWHR system.

Because the sustainability efforts required by CALGreen have become a starting point, more and more projects in California are inspired to pursue additional sustainability measures and initiatives, such as Leadership in Energy and Environmental Design (LEED), the National Green Building Standard (NGBS)(ICC-700), the WELL Building Standard (WELL), and many others. LEED v4 is a broadly applicable rating system that encompasses various structure types. Sustainable methods for construction are covered in LEED v4 as well. The National Green Building Standard (NGBS)(ICC-700) is a self-declared alternative to LEED that focuses on site development, water conservation, material resource efficiency, energy efficiency, indoor air quality, and maintenance. WELL focuses on the health and wellbeing of building occupants, putting emphasis on the effects of air quality, task lighting, and thermal comfort on productivity.

CALGreen measures overlap with many practices in LEED’s water efficiency, sustainable sites, and materials & resources categories. WELL’s energy efficiency category overlaps significantly with CALGreen requirements. And NGBS encourages many of the same site development — specifically drainage mitigation — practices required by CALGreen. Due to the relative compatibility of CALGreen and these other initiatives, many building owners are taking the certification leap (one indicator of this: 14% of California’s buildings are LEED Certified).

This behavior demonstrates that market pressures and environmental concerns have made sustainable controls for new construction a “must.” Adaptive measures like CALGreen aim to regulate energy use, water consumption, and waste creation. As CALGreen evolves, it will continue to do so more efficiently and provide a great foundation for buildings interested in pursuing more in-depth sustainability (through LEED, for example). Because of this, it’s clear that CALGreen and other sustainable controls are the key to market prosperity and environmental longevity.


Additional Resources:

Review The CALGreen building code in its entirety here:

Get a more in-depth understanding of how the California Energy Commission tracks energy use for the state here:

This document from the university of Michigan provides a statistical representation of the increase in demand for housing: