2025 Nonresidential Solar PV

Section 140.10(a) -PDF of the 2025 Energy Code requires solar photovoltaic (PV) systems for all newly constructed nonresidential buildings, with five exceptions (see below).  

These requirements apply to buildings where at least 80 percent of the total floor area (conditioned or not) serves one or more of building types specified in Table 140.10-A, including mixed-occupancy buildings.  

These building types include:  

• Events & exhibits
• Library
• Hotel/motel
• Multifamily buildings with 3 or more habitable stories
• Office, financial institution, unleased tenant space, medical office building/clinic
• Restaurants
• Retail, grocery
• Religious worship
• Sports & recreation
• School
• Warehouse 

These requirements do not apply to: 

• Additions
• Alterations
• Unconditioned buildings (except unoccupied or unused first-time tenant improvement spaces since they meet the definition of newly constructed buildings) 

Yes. There are five exceptions that exclude nonresidential buildings from the solar PV requirements 

• Total SARA is less than 3 percent of the conditioned floor area
• Minimum required solar PV system capacity is less than 4 kWdc
• SARA is less than 80 contiguous square feet
• The enforcement authority determines the solar PV system cannot meet the American Society of Civil Engineers Standard 7-16, Chapter 7, Snow Loads requirements
• For nonresidential and hotel/motel multitenant buildings, the PV capacity is calculated using Equation 140.10-A excluding tenant spaces that satisfy all the following:
  • 2,000 square feet or less of conditioned floor area
  • Individual HVAC system
  • Individual utility meter
  • Exception does not apply to buildings where either:
    • CEC has approved a community solar program per §10-115; or
    • Loading serving entity provides a program that compensates PV generation through virtual energy bill credits for occupants of nonresidential and hotel/motel tenant spaces from netting of energy generation and consumption 

No. Solar PV systems can be installed on the building’s SARA, ground-mounted on the property, or mounted atop a carport installed on the lot. Note: an alternative to installing solar PV on-site is to comply with community solar requirements when using the performance compliance approach if the CEC has approved a community solar program for the building type in the area where the building is located. 

The solar-ready requirements under Section 110.10(b)-(d) – PDF are mandatory, but only apply to nonresidential buildings that do not require a solar PV system (see Section 110.10(a) - PDF): 

• Newly constructed nonresidential buildings up to three habitable stories, other than I-2 and I-2.1 occupancies shall comply with Section 110.10(b)-(d) – PDF
• Newly constructed hotel/motel occupancies with up to ten habitable stories shall comply with Section 110.10(b)-(d) – PDF
• Additions where the total roof area is increased by more than 2,000 square feet  

Yes. Buildings where at least 80 percent of the floor area (including unconditioned space) serves one of the space types listed in Table 140.10-A - PDF, such as warehouse or office, including the conditioned spaces supporting these areas (e.g., restrooms, closets, corridors), shall have a solar PV system installed. The PV system size is determined by Equation 140.10-A - PDF, or solar access roof area (SARA), whichever is smaller. Note: Equation 140.10-A only considers conditioned floor area. Exceptions to Section 140.10 - PDF may apply

Yes. Per Section 140.10(a) - PDF of the 2025 Energy Code, newly constructed nonresidential buildings where at least 80 percent of the floor area of the building serves one or more of the building types listed in Table 140.10-A – PDF must install PV. Table 140.10-A includes office, restaurants, retail and sports & recreation space types. Also, a battery energy storage system may be required per Section 140.10(b) – PDF. Nonresidential spaces are generally defined in Section 100.1(b) – PDF. Although “amenity building” is not listed in Table 140.10-A, some of these spaces may fall under restaurant or retail. The building department should confirm the space types of the amenity building.

Yes. First time tenant improvements (TI) for individual spaces where the building space has never been used or occupied for any purpose meets the definition of a newly constructed building per the Energy Code Section 100.1 - PDF. The 2025 Energy Code requirements apply to permit applications for first time tenant improvements for each space in a building that are submitted on or after January 1, 2026. All newly constructed building types specified in Table 140.10-A must meet the applicable solar PV and battery energy storage system requirements of Section 140.10 – PDF the 2025 Energy Code. Some exceptions may apply. The building space occupancy status is determined by the local enforcement agency.  

No. A tenant improvement in an existing building tenant space that was previously occupied would be considered an alteration. Alterations need to comply with the applicable requirements in Section 141.0(b) - PDF depending on the scope of work. An alteration is any change to a component that is regulated by the Energy Code, including water-heating system, ventilation system, space-conditioning system, indoor, outdoor, and sign lighting, electrical power distribution system, envelope, and any covered process. For alterations that change the occupancy classification of the tenant space, the requirements per Section 141.0 – PDF apply to the new occupancy type.

No. Unconditioned floor area is considered part of the 80 percent trigger for spaces listed in Table 140.10-A - PDF for nonresidential solar PV requirements. However, only the conditioned floor area of the space listed in Table 140.10-A is considered when calculating the required solar PV system size per Equation 140.10-A - PDF. SARA must also be calculated. The smaller of the two calculations determines the solar PV system capacity, or required solar PV as calculated using approved software in the performance approach. Some exceptions may apply.  

No. The prescriptive requirements for solar PV and battery energy storage system (BESS) apply to conditioned warehouses depending on climate zone. 

No. The prescriptive requirements for solar PV and battery energy storage system (BESS) only apply to newly constructed buildings.

Yes. Per Section 110.10(a) – PDF, solar-ready is required since there is only one habitable story in the 12-story building.

No. Exception 5 to Section 110.10(b)1B - PDF applies to areas that are designed and approved for vehicular traffic and parking. The required solar-ready zone should be no less than 15 percent of the total roof area of the small office. 

See the Blueprint for more information, including articles and frequently asked solar PV questions about the 2025 Energy Code.