Queen Anne Flats
Multifamily Housing in Seattle, WA · 521 2ND AVE W · 98119
At a glance
Queen Anne Flats is a 23,060-square-foot multifamily housing building at 521 2ND AVE W in Seattle, Washington, built in 2014. In its 2025 Seattle benchmarking disclosure it reported an ENERGY STAR score of 91 out of 100 (grade A), a site energy-use intensity of 34.2 kBtu/ft² and 20 tCO₂e of greenhouse-gas emissions. That score is higher than 49% of the 1,652 scored multifamily housing buildings in Seattle.
Seattle Energy Benchmarking Ordinance (SMC 22.920) · reporting year 2025
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 91 (band A) |
| Site EUI | 34.2 kBtu/ft² |
| Source EUI | 71.0 kBtu/ft² |
| GHG emissions | 20 tCO₂e |
| GHG intensity | 0.8 kgCO₂e/ft² |
| Electricity | 135,586 kWh |
| Natural gas | 3,249 therms |
| Gross floor area | 23,060 sq ft |
| Source record | seattle:50097:2025 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2025latest | 91 | -1 | 34.2 kBtu/ft² | 20 tCO₂e |
| 2024 | 92 | +3 | 33.0 kBtu/ft² | 19 tCO₂e |
| 2023 | 89 | -3 | 33.4 kBtu/ft² | 19 tCO₂e |
| 2022 | 92 | 33.1 kBtu/ft² | 19 tCO₂e | |
| 2021 | — | — | — | |
| 2020 | 95 | ±0 | 29.7 kBtu/ft² | 17 tCO₂e |
| 2019 | 95 | +5 | 30.0 kBtu/ft² | 16 tCO₂e |
| 2018 | 90 | +6 | 33.4 kBtu/ft² | 19 tCO₂e |
| 2017 | 84 | 37.5 kBtu/ft² | 21 tCO₂e |
Compliance context
Seattle Energy Benchmarking Ordinance (SMC 22.920)
Seattle's Building Emissions Performance Standard (adopted 2023) applies to buildings over 20,000 sq ft: benchmarking verification is due 2027–2030 and initial emissions targets 2031–2035, reaching net zero by 2041–2050, with fines for non-compliance.
Ownership
No owning organisation shown. Names of private individuals in the disclosure are not published here.
Own or manage this building? Claim it to correct the record and get compliance alerts.
Location
- Address
- 521 2ND AVE W
- City
- Seattle
- State
- Washington
- ZIP
- 98119
- Coordinates
- 47.62397, -122.35972
Within ~1 km
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See also: most efficient in Seattle · biggest emitters
How does Queen Anne Flats compare with other multifamily housing buildings in Seattle?
The latest disclosures cover 1,971 multifamily housing buildings in Seattle, out of 3,871 buildings citywide. Queen Anne Flats's ENERGY STAR score of 91 compares with an average of 83 across the 1,652 that report a score; it scores higher than 49% of them and lower than 48%. Its site EUI of 34.2 kBtu/ft² is roughly in line with the average of 34.9 kBtu/ft² — it uses less energy per square foot than the typical building in that group. Its emissions intensity of 0.8 kgCO₂e/ft² is about 21% above the group average of 0.7 kgCO₂e/ft².
At 23,060 sq ft, it is about 73% below the average floor area of 86,468 sq ft for those buildings. It was built in 2014, 31 years later than the group's average year built (1983). 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 Queen Anne Flats's energy performance changed over time?
BuildingCensus holds 9 Seattle disclosures for Queen Anne Flats, covering report years 2017–2025. Its ENERGY STAR score went from 84 in 2017 to 91 in 2025 (+7 points); its best year on file was 2019, at 95. Site EUI moved from 37.5 kBtu/ft² (2017) to 34.2 kBtu/ft² (2025), a 9% decrease. Reported emissions went from 21 tCO₂e to 20 tCO₂e over the same span (down 8%).
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 Seattle, 69% 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. Queen Anne Flats's 34.2 kBtu/ft² across 23,060 sq ft works out to about 0.8 billion Btu (231 MWh-equivalent) in 2025. Its source EUI of 71.0 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 135,586 kWh of electricity and 3,249 therms of natural gas for the year.
Which law requires Queen Anne Flats to report its energy use?
Queen Anne Flats reports under the Seattle Energy Benchmarking Ordinance (SMC 22.920), the legal basis of Seattle's Building Energy Benchmarking program, which publishes each covered building's annual benchmarking results. The record shown here is the report-year 2025 disclosure (source record seattle:50097:2025). Seattle's Building Emissions Performance Standard (adopted 2023) applies to buildings over 20,000 sq ft: benchmarking verification is due 2027–2030 and initial emissions targets 2031–2035, reaching net zero by 2041–2050, with fines for non-compliance.
More multifamily housing buildings in Seattle
- Queen's Court Condo· 23,052 sq ft
- Queen Anne Exchange· 23,040 sq ft
- Dorothy Day House· 23,015 sq ft · EUI 75.8 kBtu/ft²
- The Hawaiian Apartment· 22,992 sq ft · score 79 (B)
- Dexter Place Condominium· 22,984 sq ft · score 100 (A)
- West Winds Apts· 22,984 sq ft · score 47 (D)
- Multifamily Housing buildings in Seattle· 1,971 benchmarked
- All Seattle benchmarked buildings· Seattle Energy Benchmarking Ordinance (SMC 22.920)
- Most efficient large buildings in Seattle
- Least efficient large buildings in Seattle
- Biggest emitters in Seattle
Frequently asked questions
What is Queen Anne Flats's energy grade?
Queen Anne Flats scores 91 out of 100 on ENERGY STAR — band A, high performer (85–100) — in its 2025 Seattle disclosure. Scores are national percentiles against similar buildings; 75+ qualifies for ENERGY STAR certification.
How much energy does Queen Anne Flats use?
Its 2025 site energy-use intensity was 34.2 kBtu/ft² (71.0 kBtu/ft² source) across 23,060 sq ft, including 135,586 kWh of electricity and 3,249 therms of natural gas.
What are Queen Anne Flats's carbon emissions?
Queen Anne Flats reported 20 tCO₂e of greenhouse-gas emissions (0.8 kgCO₂e/ft²) for 2025.
Where is Queen Anne Flats?
Queen Anne Flats is at 521 2ND AVE W, in Seattle, Washington 98119. Its coordinates are 47.62397, -122.35972 (latitude, longitude), as published in the Building Energy Benchmarking file.
How big is Queen Anne Flats and when was it built?
Queen Anne Flats has 23,060 sq ft of gross floor area, as reported in its 2025 disclosure. The disclosure lists 2014 as its year built. It is classed as multifamily housing.
Is Queen Anne Flats covered by the Seattle Energy Benchmarking Ordinance (SMC 22.920)?
Yes — it appears in the 2025 Building Energy Benchmarking disclosure, which lists the buildings reporting under the Seattle Energy Benchmarking Ordinance (SMC 22.920).
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About this data
Source: Building Energy Benchmarking (Seattle Energy Benchmarking Ordinance (SMC 22.920)), as published October 2, 2026. See the methodology for how records are matched, cleaned and scored.
Cite as: BuildingCensus, “Queen Anne Flats, Seattle, Washington — 2025 benchmarking disclosure”, https://buildingcensus.com/buildings/seattle/queen-anne-flats-d8020e32 (data as of October 2, 2026).