Casa Bonita Apartments

How does Casa Bonita Apartments compare with other multifamily (5+ units) buildings in Berkeley?

The latest disclosures cover 202 multifamily (5+ units) buildings in Berkeley, out of 440 buildings citywide. Casa Bonita Apartments's ENERGY STAR score of 91 compares with an average of 92 across the 156 that report a score; it scores higher than 19% of them and lower than 78%. Its site EUI of 42.4 kBtu/ft² is about 29% above the average of 32.9 kBtu/ft² — it uses more energy per square foot than the typical building in that group.

At 19,599 sq ft, it is about 41% below the average floor area of 33,316 sq ft for those buildings.

How has Casa Bonita Apartments's energy performance changed over time?

BuildingCensus holds 4 Berkeley disclosures for Casa Bonita Apartments, covering report years 2022–2025. Its ENERGY STAR score went from 72 in 2023 to 91 in 2025 (+19 points). Site EUI moved from 61.4 kBtu/ft² (2022) to 42.4 kBtu/ft² (2025), a 31% decrease.

What does an ENERGY STAR score of 91 mean?

ENERGY STAR scores run from 1 to 100 and are computed by the EPA's Portfolio Manager as a percentile against similar buildings nationwide, adjusted for climate, size and use: a score of 91 means the building performs better than about 91% of its national peers. BuildingCensus bands the score into report-card grades; 91 falls in band A — high performer (85–100). Scores of 75 or higher meet the threshold for ENERGY STAR certification; certification itself is a separate, verified application that the disclosure does not record. In Berkeley, 82% of scored buildings are at 75 or above.

Site energy-use intensity (EUI) is the energy a building uses on site in a year divided by its floor area, in thousand Btu per square foot — lower is more efficient. Casa Bonita Apartments's 42.4 kBtu/ft² across 19,599 sq ft works out to about 0.8 billion Btu (244 MWh-equivalent) in 2025. Its source EUI of 58.3 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 45,254 kWh of electricity and 6,769 therms of natural gas for the year.

Which law requires Casa Bonita Apartments to report its energy use?

Casa Bonita Apartments reports under BESO (BMC Chapter 19.81), the legal basis of Berkeley's Building Emissions Saving Ordinance, which publishes each covered building's annual benchmarking results. The record shown here is the report-year 2025 disclosure (source record berkeley:7630:2025). Berkeley's BESO requires annual benchmarking for commercial and multifamily buildings of 15,000 sq ft or more, with energy assessments at time of listing and every five years for buildings of 25,000 sq ft or more.