This CASE Report for outdoor lighting consists of three submeasures: nonresidential lighting zone reclassification, nonresidential lighting power allowances for parking lots, and multifamily outdoor lighting power allowances.
Nonresidential Lighting Zone Reclassification
The outdoor lighting zone reclassification measure is proposed to align the California lighting zones with current industry standards employed across North America. Currently, lighting zones in California are classified with a United States (U.S.) Census-based approach which dictates lighting zones using the population–based classification of an area as “rural” or “urban“. This has resulted in over lighting many areas throughout the state. There are five lighting zones:
- Lighting Zone 0 (LZ0): Includes undeveloped areas with essentially no artificial lighting.
- Lighting Zone 1 (LZ1): Includes developed portions of government designated parks, recreation areas, and wildlife preserves.
- Lighting Zone 2 (LZ2): Is defined as “rural” areas.
- Lighting Zone 3 (LZ3): Is defined as “urban” areas.
- Lighting Zone 4 (LZ4): Includes areas with maximum artificial lighting such as Times Square in New York City. Currently, no areas within California fall under LZ4.
This proposal revisits the current population-based approach and aims to provide more discretized lighting zone applications based on the U.S Census classifications; this would reduce energy use throughout California while minimizing sky glow2 and light trespass.3 Specifically, this proposal updates the lighting zone definitions to more closely match the Illuminating Engineering Society’s (IES) lighting zone definitions. The updated definitions would still rely on population density, but would specifically shift “rural” areas from LZ2 to LZ1:
- LZ0: This is unchanged.
- LZ1: Would still include developed portions of government designated parks, recreation areas, and wildlife preserves, but “rural” areas previously part of LZ2 would now be included here, along with residential and agricultural areas. “Rural” is defined as less than 2,500 people per square mile.
- Lighting Zone 2 (LZ2): Was previously “rural” areas but is now “urban cluster” areas as well as mixed use residential, light commercial, and industrial areas. “Urban clusters” are defined as areas with between 2,500 and 50,000 people per square mile.
- Lighting Zone 3 (LZ3): is still defined as “urban” areas, but now specifically includes high intensity commercial, entertainment centers, and heavy industrial and manufacturing. “Urban” areas are defined as greater than 50,000 people per square mile.
- Lighting Zone 4 (LZ4): This is unchanged.
No change to the lighting power allowances (LPAs) associated with the current lighting zones have been proposed; this submeasure simply seeks to reclassify existing areas into more appropriate lighting zones.4 This proposed change, which would modify Section 10-114, would impact new construction and alterations and additions in California.
A new section would be added to the nonresidential lighting compliance manual to document that luminaires installed on the project meet the backlight, uplight, and glare (BUG) rating requirements listed in Title 24, Part 11 (CALGreen). Luminaires installed within two mounting heights from the property line would be documented to confirm that they meet the CALGreen backlight and glare ratings based on their orientation towards the property lines. This would not result in additional field verification or acceptance tests beyond those that currently exist.
Nonresidential Lighting Power Allowances for General Hardscape
The LPAs for the general hardscape submeasure would update the existing prescriptive requirements for outdoor lighting and would impact new construction, alterations, and additions across California. This submeasure would update the general hardscape LPAs for areas affected by the light level recommendations in the latest version of the IES Recommended Practice (RP) 8-18 Addendum 1 to Chapter 17 (Illuminating Engineering Society 2020). This submeasure incorporates recent research that suggests task visibility plateaus at lower lighting levels than previously recommended, which prompted IES to revise the parking lot lighting levels to align with those recommended by IES prior to the IES RP-20-14 publication (republished as ANSI/IES RP-8-18 Chapter 17),5 which increased the recommended lighting levels. The Statewide CASE Team is proposing to reduce the prescriptive exterior lighting LPAs to reflect the revised parking lot lighting level recommendations.
This submeasure also reassesses the need to distinguish between asphalt and concrete surfaces, which currently have different LPA specifications in Title 24, Part 6. The pavement distinction is proposed to be removed from Table 140.7-A to simplify this code measure. The general hardscape LPAs would be updated to reflect luminaires available on the market at the time of analysis. No new field verification or acceptance tests beyond those that currently exist would be required, and the proposal would not result in new system or technology requirements.
This submeasure includes a new lighting allowance for general hardscape applications with security cameras; this would allow for lighting levels in general hardscape applications to be increased to improve the sense of safety within the area. The allowance would also ensure that the minimum illumination requirements of a security camera with color detection capabilities can be achieved during non-occupied times when the lighting levels have been reduced per Title 24, Part 6, Section 130.2. Security camera technology, available in 2019 at the time of this analysis, is capable of functioning in low nighttime lighting conditions to identify people, animals, and objects of concern within the general hardscape area. The Statewide CASE Team’s analysis found that the average cameras with color detection capabilities require an average of 0.33 lux at 50 IRE F1.6, to properly identify colors during nighttime lighting levels. Cameras with black and white detection capabilities require less ambient lighting, while cameras with infrared detection do not require any additional lighting. Refer to Appendix O for more information on current security camera technology.
The Statewide CASE Team is also proposing to update the legacy hardscape ornamental lighting 100–watt limit to 50 watts to align with the current LED baseline.
The Statewide CASE Team is also proposing to replace the term “cutoff” with “shielding” in Section 130.2(b). This is not a substantive update, but it is beneficial as it aligns code language with industry terminology.
The ornamental hardscape special application listed in Table 140.7-B is proposed to be amended to reflect the 50-watt luminaire qualification incorporated in the 2019 Title 24, Part 6, Section 100.1 definition.
Multifamily Outdoor Lighting Power Allowances
The Energy Commission is considering consolidation of low-rise and high-rise multifamily requirements under a new multifamily section in 2022 Title 24, Part 6. The multifamily outdoor LPAs submeasure proposes new LPAs for several new code sections that would be placed in the multifamily chapter of code being proposed for the Multifamily Chapter Restructuring Final CASE Report. This submeasure creates limits for outdoor lighting that are more appropriate for circumstances and conditions associated with the residential nature of multifamily buildings.
This proposal was developed using a similar method to previous nonresidential outdoor lighting code updates. The current nonresidential LPA requirements are used as a base case for the analyses. The 2019 nonresidential outdoor lighting power allowance CASE Study, which describes the methodology for the 2019 code cycle, is available on the Title24stakeholders.com website (Statewide CASE Team 2017).
The proposed technology level used to establish the 2022 multifamily LPA values is based on luminaires that are cost effective at the time of the analysis. Costs are expected to continue to decline before the effective date of the standards. The efficacies of the products used to develop the 2019 LPAs have been updated for the applications that fall under the scope of Table 140.7-A and Table 140.7-B.
Target illumination levels are based upon current IES RP documents recommended lighting levels that set light level guidelines for outdoor spaces and other industry standards for all target illuminance levels. The same recommend practice documents are employed for both the nonresidential and the multifamily general hardscape allowance calculations. Certain allowances that are currently included in Table 140.7-B are not included in the proposed multifamily allowance tables as the use of these additional allowances are incompatible with multifamily residential environments.
This submeasure also makes a change to the setback requirements for outdoor lighting controls in Section 130.2 to match the IES recommendations for late-night setback design criteria. The current code was established with a 50 percent reduction, but the IES recommendations include a 60 percent reduction from the main criteria levels. This measure incorporates this 60 percent reduction.
The submeasure also simplifies the LPA calculation approach by moving from a three-factor method (area wattage allowance, perimeter wattage allowance, and initial wattage allowance) to a two-factor approach (area wattage allowance and initial wattage allowance). The removal of the perimeter wattage allowance reduces the documentation for the design and code compliance steps and would make the calculation of the LPA easier and faster to complete. This modification would result in a substantial change in the allowance values included in the LPA table for general hardscape in Table 140.7-A, but would have no impact to the allowance values in the additional allowances Table 140.7-B.
Measure proposals, supporting documents, and other outside references will be made public as they become available.
- Draft CASE Report – Nonresidential Outdoor Lighting Sources
- Final CASE Report – Noresidential Outdoor Lighting Sources
Round Two Utility-Sponsored Stakeholder Meeting Materials
- Submeasure Summary – Nonresidential Outdoor Lighting Zone Reclassification
- Submeasure Summary – Multifamily Outdoor LPA
- Presentation – March 3 – Lighting Utility-Sponsored Stakeholder Meeting
- Notes – March 3 – Lighting Utility-Sponsored Stakeholder Meeting
Round One Utility-Sponsored Stakeholder Meeting Materials
- Submeasure Summary – Nonresidential Lighting Zone Reclassification
- Submeasure Summary – Nonresidential Lighting Power Allowances for Parking Lots
- Submeasure Summary – Multifamily Outdoor Lighting Power Allowances
- Sept 5 – Nonresidential and Multifamily Outdoor Sources and Daylighting Stakeholder Meeting Presentation
- Notes – Sept 5 – Nonresidential and Multifamily Outdoor Sources and Daylighting Stakeholder Meeting
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The Statewide CASE Team values input from all stakeholders engaged in the Title 24, Part 6 code change process. We encourage the open exchange of code change comments and concerns.
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