At a glance
139 Main St is a 41,857-square-foot office building in Cambridge, Massachusetts, built in 2019. In its 2024 Cambridge benchmarking disclosure it reported an ENERGY STAR score of 80 out of 100 (grade B), a site energy-use intensity of 59.5 kBtu/ft² and 152 tCO₂e of greenhouse-gas emissions. That score is higher than 66% of the 94 scored office buildings in Cambridge.
BEUDO · reporting year 2024
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 80 (band B) |
| Site EUI | 59.5 kBtu/ft² |
| Source EUI | 106.0 kBtu/ft² |
| GHG emissions | 152 tCO₂e |
| GHG intensity | — |
| Electricity | 304,928 kWh |
| Natural gas | 14,507 therms |
| Water use | 211 kgal |
| Gross floor area | 41,857 sq ft |
| Source record | cambridge:B1315:2024 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2024latest | 80 | -7 | 59.5 kBtu/ft² | 152 tCO₂e |
| 2023 | 87 | -1 | 46.8 kBtu/ft² | 122 tCO₂e |
| 2022 | 88 | ±0 | 46.1 kBtu/ft² | 120 tCO₂e |
| 2021 | 88 | +4 | 47.1 kBtu/ft² | 122 tCO₂e |
| 2020 | 84 | +13 | 57.2 kBtu/ft² | 143 tCO₂e |
| 2019 | 71 | 71.3 kBtu/ft² | 175 tCO₂e | |
| 2018 | — | — | 0 tCO₂e | |
| 2017 | — | — | 0 tCO₂e | |
| 2016 | — | — | 0 tCO₂e | |
| 2015 | — | — | 0 tCO₂e |
Compliance context
BEUDO
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).
Ownership
MIT 139 MAIN ST FEE OWNER LLC
Own or manage this building? Claim it to correct the record and get compliance alerts.
Location
- Address
- 139 Main St
- City
- Cambridge
- State
- Massachusetts
- Coordinates
- 42.36230, -71.08230
Within ~1 km
Nearby benchmarked buildings
- 100 Cambridge Side Placescore —
Enclosed Mall · 747,697 sq ft
- 50-60 Binney STscore —
Mixed Use Property · 532,739 sq ft
- 325 Main Stscore 87
Office · 494,512 sq ft
- 145 Broadwayscore 91
Office · 490,000 sq ft
- 314 Main St.score 80
Office · 482,220 sq ft
- 303 Binney Stscore —
Laboratory · 480,000 sq ft
See also: most efficient in Cambridge · biggest emitters
How does 139 Main St compare with other office buildings in Cambridge?
The latest disclosures cover 117 office buildings in Cambridge, out of 902 buildings citywide. 139 Main St's ENERGY STAR score of 80 compares with an average of 64 across the 94 that report a score; it scores higher than 66% of them and lower than 32%. Its site EUI of 59.5 kBtu/ft² is about 24% below the average of 78.7 kBtu/ft² — it uses less energy per square foot than the typical building in that group.
At 41,857 sq ft, it is about 65% below the average floor area of 121,167 sq ft for those buildings. It was built in 2019, 54 years later than the group's average year built (1965). Across all 24 jurisdictions BuildingCensus covers, the 15,264 office buildings average an ENERGY STAR score of 73 and a site EUI of 59.3 kBtu/ft².
How has 139 Main St's energy performance changed over time?
BuildingCensus holds 10 Cambridge disclosures for 139 Main St, covering report years 2015–2024. Its ENERGY STAR score went from 71 in 2019 to 80 in 2024 (+9 points); its best year on file was 2021, at 88. Site EUI moved from 71.3 kBtu/ft² (2019) to 59.5 kBtu/ft² (2024), a 17% decrease.
What does an ENERGY STAR score of 80 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 80 means the building performs better than about 80% of its national peers. BuildingCensus bands the score into report-card grades; 80 falls in band B — above median (70–84). 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. 139 Main St's 59.5 kBtu/ft² across 41,857 sq ft works out to about 2.5 billion Btu (730 MWh-equivalent) in 2024. Its source EUI of 106.0 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 304,928 kWh of electricity, 14,507 therms of natural gas and 211 thousand gallons of water for the year.
Which law requires 139 Main St to report its energy use?
139 Main St 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:B1315:2024). 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).
More office buildings in Cambridge
- 485 Mass Ave.· 39,961 sq ft · score 15 (D)
- 130 Prospect Street· 37,916 sq ft · score 90 (A)
- 77 Fawcett Street· 34,842 sq ft · score 11 (D)
- 497-507 Massachusetts Ave· 34,388 sq ft · score 12 (D)
- 5 Western Avenue· 34,055 sq ft · score 98 (A)
- 344 Broadway· 33,909 sq ft · score 69 (C)
- Office buildings in Cambridge· 117 benchmarked
- All Cambridge benchmarked buildings· BEUDO
- Most efficient large buildings in Cambridge
- Least efficient large buildings in Cambridge
- Biggest emitters in Cambridge
Frequently asked questions
What is 139 Main St's energy grade?
139 Main St scores 80 out of 100 on ENERGY STAR — band B, above median (70–84) — in its 2024 Cambridge disclosure. Scores are national percentiles against similar buildings; 75+ qualifies for ENERGY STAR certification.
How much energy does 139 Main St use?
Its 2024 site energy-use intensity was 59.5 kBtu/ft² (106.0 kBtu/ft² source) across 41,857 sq ft, including 304,928 kWh of electricity and 14,507 therms of natural gas.
What are 139 Main St's carbon emissions?
139 Main St reported 152 tCO₂e of greenhouse-gas emissions for 2024.
Where is 139 Main St?
139 Main St is in Cambridge, Massachusetts. Its coordinates are 42.36230, -71.08230 (latitude, longitude), as published in the Building Energy Use Disclosure Ordinance (BEUDO) file.
How big is 139 Main St and when was it built?
139 Main St has 41,857 sq ft of gross floor area, as reported in its 2024 disclosure. The disclosure lists 2019 as its year built. It is classed as office.
Is 139 Main St covered by BEUDO?
Yes — it appears in the 2024 Building Energy Use Disclosure Ordinance (BEUDO) disclosure, which lists the buildings reporting under BEUDO.
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About this data
Source: Building Energy Use Disclosure Ordinance (BEUDO) (BEUDO), as published October 2, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “139 Main St, Cambridge, Massachusetts — 2024 benchmarking disclosure”, https://buildingcensus.com/buildings/cambridge/139-main-st-b86245e0 (data as of October 2, 2026).