129 Franklin Street

How does 129 Franklin Street compare with other multifamily housing buildings in Cambridge?

The latest disclosures cover 187 multifamily housing buildings in Cambridge, out of 902 buildings citywide. 129 Franklin Street's ENERGY STAR score of 98 compares with an average of 75 across the 155 that report a score; it scores higher than 79% of them and lower than 18%. Its site EUI of 35.5 kBtu/ft² is about 38% below the average of 56.9 kBtu/ft² — it uses less energy per square foot than the typical building in that group.

At 243,166 sq ft, it is about 84% above the average floor area of 132,415 sq ft for those buildings. It was built in 2001, 28 years later than the group's average year built (1973). Across all 24 jurisdictions BuildingCensus covers, the 59,945 multifamily housing buildings average an ENERGY STAR score of 70 and a site EUI of 59.0 kBtu/ft².

How has 129 Franklin Street's energy performance changed over time?

BuildingCensus holds 10 Cambridge disclosures for 129 Franklin Street, covering report years 2015–2024. Its ENERGY STAR score went from 97 in 2015 to 98 in 2024 (+1 points); its best year on file was 2020, at 98. Site EUI moved from 37.4 kBtu/ft² (2015) to 35.5 kBtu/ft² (2024), a 5% decrease. Reported emissions went from 574 tCO₂e to 520 tCO₂e over the same span (down 9%).

What does an ENERGY STAR score of 98 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 98 means the building performs better than about 98% of its national peers. BuildingCensus bands the score into report-card grades; 98 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 Cambridge, 50% 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. 129 Franklin Street's 35.5 kBtu/ft² across 243,166 sq ft works out to about 8.6 billion Btu (2,530 MWh-equivalent) in 2024. Its source EUI of 60.5 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 946,436 kWh of electricity, 53,981 therms of natural gas and 5,401 thousand gallons of water for the year.

Which law requires 129 Franklin Street to report its energy use?

129 Franklin Street reports under BEUDO, the legal basis of Cambridge's Building Energy Use Disclosure Ordinance (BEUDO), which publishes each covered building's annual benchmarking results. The record shown here is the report-year 2024 disclosure (source record cambridge:B1002:2024). Cambridge's 2023 BEUDO amendments require non-residential buildings of 100,000+ sq ft to reach net-zero emissions by 2035 (reductions starting 2026) and those of 25,000–100,000 sq ft by 2050 (starting 2030).