509 First Apartments
Multifamily Housing in Seattle, WA · 509 1ST AVE W · 98119
Seattle Energy Benchmarking Ordinance (SMC 22.920) · reporting year 2025
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 100 (band A) |
| Site EUI | 33.5 kBtu/ft² |
| Source EUI | 73.8 kBtu/ft² |
| GHG emissions | 16 tCO₂e |
| GHG intensity | 0.7 kgCO₂e/ft² |
| Electricity | 140,065 kWh |
| Natural gas | 2,498 therms |
| Gross floor area | 29,158 sq ft |
| Source record | seattle:49827:2025 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2025latest | 100 | ±0 | 33.5 kBtu/ft² | 16 tCO₂e |
| 2024 | 100 | +1 | 32.2 kBtu/ft² | 15 tCO₂e |
| 2023 | 99 | ±0 | 36.0 kBtu/ft² | 18 tCO₂e |
| 2022 | 99 | -1 | 37.8 kBtu/ft² | 20 tCO₂e |
| 2021 | 100 | +1 | 35.4 kBtu/ft² | 22 tCO₂e |
| 2020 | 99 | -1 | 37.3 kBtu/ft² | 22 tCO₂e |
| 2019 | 100 | +1 | 37.7 kBtu/ft² | 24 tCO₂e |
| 2018 | 99 | ±0 | 38.1 kBtu/ft² | 21 tCO₂e |
| 2017 | 99 | -1 | 32.4 kBtu/ft² | 23 tCO₂e |
| 2016 | 100 | ±0 | 25.9 kBtu/ft² | 21 tCO₂e |
| 2015 | 100 | 26.0 kBtu/ft² | 20 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
- 509 1ST AVE W
- City
- Seattle
- State
- Washington
- ZIP
- 98119
- Coordinates
- 47.62365, -122.35832
Within ~1 km
Nearby benchmarked buildings
- Climate Pledge Arenascore —
Indoor Arena · 932,000 sq ft
- Third And Broad Bldgscore 94
Office · 396,626 sq ft
- Armory - Seattle Centerscore —
Other · 396,085 sq ft
Multifamily Housing · 308,940 sq ft
- Expo Apartmentsscore 97
Multifamily Housing · 301,831 sq ft
- Avalon Queen Annescore 98
Multifamily Housing · 290,520 sq ft
See also: most efficient in Seattle · biggest emitters
Frequently asked questions
What is 509 First Apartments's energy grade?
509 First Apartments scores 100 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 509 First Apartments use?
Its 2025 site energy-use intensity was 33.5 kBtu/ft² (73.8 kBtu/ft² source) across 29,158 sq ft, including 140,065 kWh of electricity and 2,498 therms of natural gas.
What are 509 First Apartments's carbon emissions?
509 First Apartments reported 16 tCO₂e of greenhouse-gas emissions (0.7 kgCO₂e/ft²) for 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.
Working with Seattle building benchmarking records? Pro adds alerts, change history and CSV export ($49/mo); Enterprise adds full national files, the API and an MCP server for AI tools.
Dataset updated . Source: Building Energy Benchmarking disclosure, record seattle:49827:2025.