Trio
Multifamily Housing in Seattle, WA · 3104 WESTERN AVE · 98121
At a glance
Trio is a 131,500-square-foot multifamily housing building at 3104 WESTERN AVE in Seattle, Washington, built in 2006. In its 2025 Seattle benchmarking disclosure it reported an ENERGY STAR score of 90 out of 100 (grade A), a site energy-use intensity of 30.4 kBtu/ft² and 80 tCO₂e of greenhouse-gas emissions. That score is higher than 47% 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 | 90 (band A) |
| Site EUI | 30.4 kBtu/ft² |
| Source EUI | 64.2 kBtu/ft² |
| GHG emissions | 80 tCO₂e |
| GHG intensity | 0.7 kgCO₂e/ft² |
| Electricity | 588,680 kWh |
| Natural gas | 13,013 therms |
| Gross floor area | 131,500 sq ft |
| Source record | seattle:25603:2025 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2025latest | 90 | -1 | 30.4 kBtu/ft² | 80 tCO₂e |
| 2024 | 91 | ±0 | 29.6 kBtu/ft² | 77 tCO₂e |
| 2023 | 91 | ±0 | 30.2 kBtu/ft² | 78 tCO₂e |
| 2022 | 91 | +4 | 30.5 kBtu/ft² | 75 tCO₂e |
| 2021 | 87 | +4 | 31.9 kBtu/ft² | 82 tCO₂e |
| 2020 | 83 | +3 | 32.4 kBtu/ft² | 84 tCO₂e |
| 2019 | 80 | +14 | 33.2 kBtu/ft² | 83 tCO₂e |
| 2018 | 66 | 36.5 kBtu/ft² | 87 tCO₂e | |
| 2017 | — | 40.3 kBtu/ft² | 105 tCO₂e | |
| 2016 | 41 | -1 | 39.0 kBtu/ft² | 102 tCO₂e |
| 2015 | 42 | 39.2 kBtu/ft² | 105 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.
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Location
- Address
- 3104 WESTERN AVE
- City
- Seattle
- State
- Washington
- ZIP
- 98121
- Coordinates
- 47.61798, -122.35603
Within ~1 km
Nearby benchmarked buildings
- Climate Pledge Arenascore —
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- Olympus Aptsscore 97
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- Avalon Belltown Towersscore 72
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- Third And Broad Bldgscore 94
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- Armory - Seattle Centerscore —
Other · 396,085 sq ft
See also: most efficient in Seattle · biggest emitters
How does Trio 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. Trio's ENERGY STAR score of 90 compares with an average of 83 across the 1,652 that report a score; it scores higher than 47% of them and lower than 51%. Its site EUI of 30.4 kBtu/ft² is about 13% below 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 0.7 kgCO₂e/ft² is roughly in line with the group average of 0.7 kgCO₂e/ft².
At 131,500 sq ft, it is about 52% above the average floor area of 86,468 sq ft for those buildings. It was built in 2006, 23 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 Trio's energy performance changed over time?
BuildingCensus holds 11 Seattle disclosures for Trio, covering report years 2015–2025. Its ENERGY STAR score went from 42 in 2015 to 90 in 2025 (+48 points); its best year on file was 2022, at 91. Site EUI moved from 39.2 kBtu/ft² (2015) to 30.4 kBtu/ft² (2025), a 22% decrease. Reported emissions went from 105 tCO₂e to 80 tCO₂e over the same span (down 24%).
What does an ENERGY STAR score of 90 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 90 means the building performs better than about 90% of its national peers. BuildingCensus bands the score into report-card grades; 90 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. Trio's 30.4 kBtu/ft² across 131,500 sq ft works out to about 4 billion Btu (1,172 MWh-equivalent) in 2025. Its source EUI of 64.2 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 588,680 kWh of electricity and 13,013 therms of natural gas for the year.
Which law requires Trio to report its energy use?
Trio 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:25603:2025). 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
- Heights On Capitol Hill· 131,050 sq ft · score 94 (A)
- Ray Apartments· 131,034 sq ft · score 99 (A)
- St James Tower Apts· 130,983 sq ft
- Mount Baker Station - North Bldg· 130,842 sq ft · score 99 (A)
- Chambery Park Condominium· 130,680 sq ft · score 37 (D)
- Lothlorien Apartments· 130,600 sq ft · score 86 (A)
- 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 Trio's energy grade?
Trio scores 90 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 Trio use?
Its 2025 site energy-use intensity was 30.4 kBtu/ft² (64.2 kBtu/ft² source) across 131,500 sq ft, including 588,680 kWh of electricity and 13,013 therms of natural gas.
What are Trio's carbon emissions?
Trio reported 80 tCO₂e of greenhouse-gas emissions (0.7 kgCO₂e/ft²) for 2025.
Where is Trio?
Trio is at 3104 WESTERN AVE, in Seattle, Washington 98121. Its coordinates are 47.61798, -122.35603 (latitude, longitude), as published in the Building Energy Benchmarking file.
How big is Trio and when was it built?
Trio has 131,500 sq ft of gross floor area, as reported in its 2025 disclosure. The disclosure lists 2006 as its year built. It is classed as multifamily housing.
Is Trio 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, “Trio, Seattle, Washington — 2025 benchmarking disclosure”, https://buildingcensus.com/buildings/seattle/trio-4a241ed9 (data as of October 2, 2026).