Every three years, the California Energy Commission (CEC) revisits its energy efficiency standards, augmenting the building code to align with recent technological advancements and the state’s new efficiency goals. The commission underwent this process again this year, identifying areas for improvement in both new construction and retrofits for residential and nonresidential properties.
With this most recent set of revisions, the commission is striving toward a pair of new state efficiency targets: achieving net zero energy for new residential construction by 2020 and for new commercial construction by 2030. Referred to as the 2016 version, these standards will go into effect January 1, 2017.
Highlights of the 2016 Standards include:
Low-Rise Residential Standards (applies to residential occupancies in buildings with 3 or fewer habitable stories above grade):
• Fenestration: No changes to prescriptive compliance areas and efficiency as compared to the 2013 Standards.
• Roof Insulation: The mandatory minimum value is decreasing from R-30 to R-22. The prescriptive requirement for designs with ducts in attic space now includes insulation at the roof plane in addition to the ceiling insulation. The goal is to keep the attic temperature close to the conditioned volume temperature, thus reducing unwanted heat gains and losses from the ducts.
• Wall Insulation: The prescriptive requirement for wood framed walls is increasing from R-13 batt + R-5 sheathing (or equivalent) to R-21 batt + R-4 sheathing (or equivalent), in most climate zones.
• Third-party field verification: No major changes from the 2013 Standards.
• “Ventilation Cooling”: The minimum cfm/floor area requirement was reduced for this prescriptive compliance requirement.
• Duct insulation: In some climate zones, the prescriptive requirement is increasing from R-6 to R-8.
• Domestic Water Heater: The “standard” system for prescriptive compliance is changing from a single 50 gallon or less gas-fired water heater (per dwelling unit) to a single gas-fired tankless water heater. Storage water heaters may also comply with the prescriptive requirements when additional energy saving measures are included in the design.
• Indoor Lighting: There are a couple of major changes: All lighting must be “high efficacy”. Therefore, there are no longer kitchen lighting power calculations, which were previously required for kitchens that included some incandescent lighting. Also, with the exception of recessed can lights, luminaires may use screw-based bulbs, as long as the bulb is labeled as meeting Title 24 high efficacy requirements. [The CEC believes that most screw-based luminaires will be equipped with LED lamps, and that most residents will continue to use LED lamps rather than change them to incandescent bulbs]
• Solar photovoltaic credit: After a limited introduction in the 2013 code, now all single-family and multi-family buildings (except in coastal Southern California) can take a performance credit for the inclusion of solar electric systems. This is a relatively simply credit, because it is based on the rated KW size of the array (i.e. an annual energy production estimate is not required). To earn a PV credit, the KW capacity must meet a certain minimum threshold, which varies by the size of the building. The performance credit varies based on climate zone and building size. The “credit” is not large (and it does not increase for systems larger than the minimum size), so don’t expect that having a PV system will allow one to build a glass house.
• Additions and Alterations: Prescriptive roof insulation reduced, prescriptive wall insulation requirement increased. However, exterior walls that line up with existing exterior walls are not required to be any thicker than the existing walls. No changes to fenestration requirements as compared to the 2013 Standards.
High-Rise Residential and Non-Residential Standards:
• Fenestration: No changes from the 2013 Standards.
• Minimum roof and wall insulation: Some relaxation of requirements. Where metal frame walls essentially had to have insulative sheathing in order to meet the minimum insulation requirement under the 2013 code, now R-25 batt in 8” metal studs meet the minimum insulation requirement.
• Prescriptive compliance roof and wall insulation: Some modest increases in insulation requirements for some assemblies in some climate zones.
• Demising walls (walls separating conditioned and unconditioned spaces): R-13 between metal framing no longer meets the requirement. R-13 batt insulation between wood framing can meet the requirement, and R-25 batt between 8” metal framing can meet the requirement. Any smaller width metal stud wall will require continuous insulative sheathing in addition to the batt insulation.
• Cool Roofs: No changes from the 2013 Standards.
• Space Conditioning Systems: Only one major change to the prescriptive compliance requirements: automatic system shut-off (interlock) at operable wall and roof openings. Doors with automatic closers are exempt. Alterations are exempt.
• Indoor lighting power: The lighting power allowances for certain interior tasks are reduced in response to advances in lighting technology. Examples: Conference/convention/multi-purpose changed from 1.4 to 1.2 watts/sq.ft., lounge changed from 1.1 to 0.9 watts/sq.ft. No changes to office area lighting power allowance.
• Indoor lighting controls: The current mandatory occupancy sensor (OS) requirement for small offices, conference rooms, classrooms and multi-purpose rooms is changed to require the use of either partial-on OS control, or “vacancy sensor” control (the latter control is where turning on the lights is totally manual, lights turn off automatically when space vacant).
• Outdoor lighting power: The lighting power allowances for certain area types is reduced in response to advances in lighting technology.
• Outdoor lighting controls: Dimming requirement expanded to include outdoor sales areas.