Energy Savings on the Way for New Construction and Major Renovations in California: New Building Code Process Begins

The next update to California’s building energy code, known as Title 24, is officially underway. Today, the California Energy Commission launches the process of updating minimum efficiency standards for new construction and major renovations that are anticipated to take effect in 2017.

This morning the commission approved an Order Instituting Rulemaking (OIR), which marks the official start of the process to develop the 2016 building energy code. The new standards are anticipated to be finalized by May 2015 and will take effect January 1, 2017.

NRDC commends the commission for initiating this important rulemaking process. While the CEC is largely on the right track, there are some areas where they are leaving potential energy savings on the table. We look forward to participating in the process over the next several months to ensure that the code includes all cost-effective efficiency measures.

What is Title 24 and What are the Benefits?

The Title 24 building energy code covers homes, offices, high-rise apartment buildings and other building types in California. It sets requirements for everything related to a building’s energy use: from the efficiency of the lighting to the amount of insulation required.

First adopted in 1977, Title 24 has delivered tremendous benefits to California over the past several decades, including saving Californians over $30 billion on their energy bills, while cutting emissions of greenhouse gases and other pollutants, reducing the need for new power plants, and cutting peak electricity demand. The standards have helped California keep per capita electricity use essentially flat over the past three decades while the rest of the country saw per capita electricity use increase by 50 percent.

Rosenfeld Curve: Per Capita Electricity Consumption in California and the U.S.

Final Rosenfeld Curve 2011.png

Most recently, the 2013 standards which went into effect on July 1, 2014, are projected to reduce energy use in new homes by an additional 25 percent, saving homeowners whose houses meet the standards over $6,000 each in reduced utility costs over the course of 30 years. The 2013 standards are also projected to save 200 million gallons of water and to avoid 170,500 tons of greenhouse gas emissions annually.

Current Update Key Step Toward Zero Net Energy Goals

Title 24 is updated every three to four years, and while each cycle introduces key improvements and modifications to the standards, the 2016 standard update is particularly important, as it will lay the groundwork for meeting California’s Zero Net Energy (ZNE) goals: that all new residential construction meet ZNE by 2020 and all new nonresidential construction meet ZNE by 2030. This means that within the next six years, all newly constructed homes in California will need to produce as much energy as they consume through a combination of energy efficiency measures and distributed renewable energy, such as solar power. Progress in the 2016 code is critical to staying on the right path to meet the ZNE goals.

How Does the Process Work?

The Title 24 process begins with intensive research and evaluation of specific measures to be added to the code. Each measure is assessed on potential energy savings, feasibility, and life cycle cost to the consumer. The majority of this analysis is conducted by California’s energy utility companies – also known as Investor Owned Utilities (IOUs) – which compile Codes and Standards Enhancement Initiatives (CASE reports) evaluating each potential measure. There already have been a series of IOU and commission staff workshops where industry, builders, raters, advocates and other groups have provided input. After the OIR is approved, the CEC will publish a draft of the updated standards anticipated this fall, followed by an official proposal for updated standards early next year. The CEC’s plans to finalize the updated standards by May 2015.

What’s Under Consideration for Title 24 2016?

The key measures under consideration for the 2016 standards include:


  • High performance walls: Increasing wall insulation requirements and requiring quality insulation installation.
  • High performance attics or ducts in conditioned space: Builders would have a choice between advanced attic efficiency measures that reduce heat lost or putting heating and cooling ducts within the conditioned space of the home
  • 100 percent high efficacy lighting: This would simplify the current code requirements while improving lighting efficiency
  • Credit for photovoltaic systems: Builders could get credit towards meeting the code’s energy savings targets for installing a solar PV system
  • Tankless water heaters: This would change the base case water heater to be a high efficiency tankless water heater.


In general, the CEC is proposing to make Title 24 equivalent to ASHRAE 90.1-2013, a national model code adopted by states other than California, in places where it has fallen behind. This includes updates to the requirements for:

  • Indoor and outdoor lighting
  • Nonresidential envelope efficiency
  • HVAC (heating, ventilation, and air conditioning) and water heating equipment efficiency

In total, the measures under consideration could save an estimated 195.3 gigawatt-hours in the first year the standards are implemented, reducing emissions equivalent to those produced by 28,000 cars. (Note that these numbers are based on preliminary estimates and are likely to change as the CASE reports are refined and finalized.)

But the CEC Should Go Further

While these measures are on the right track, there are likely additional cost-effective savings not on the table, in particular for nonresidential buildings. NRDC submitted detailed comments in response to the pre-rulemaking workshops. At a high level, the commission could be doing more in the following areas:

  • Look beyond ASHRAE 90.1-2013 for non-residential buildings: Just keeping up with the national model code is not good enough and cost-effective opportunities exist to go further. For almost 40 years, California has led the way with advanced energy efficiency requirements for commercial buildings and so it is especially disappointing that in 2014, when the state has an ambitious ZNE goal for 2030, that the commission might be content to merely keep up with last year’s national standard. 
  • Evaluate cost-effectiveness on a whole-building basis: Looking forward, both to the 2016 standards and beyond the CEC should move toward evaluating energy savings and cost-effectiveness on a whole-building basis that will lead to deeper energy savings at lower costs, rather than measure by measure.
  • Coordinate CA HERS with National: Unfortunately, California does not currently have a functional energy rating and labeling system. To facilitate this, we recommend that the commission work to harmonize the national and California Home Energy Rating System (HERS) indexes.
  • Remove current barriers for heat pump water heaters: The code needs to be updated to reflect the advances in electric water heating efficiency, specifically the emergence of high efficiency heat pump water heaters.
  • Add water conservation measures: In light of drought and the extreme need for water conservation in California, the CEC consider the inclusion of water efficiency measures in the code, such as compact hot water distribution systems.   

The update of Title 24 offers California an incredible opportunity to take energy efficiency to the next level. If the Energy Commission has the opportunity with the 2016 code to continue California’s energy efficiency legacy and achieve significant cost-effective energy savings for Californians.   

Co-authored by MAP Sustainable Energy Fellow Mia Diawara.

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