Mason & Main Building A
Multifamily Housing in Seattle, WA · 209 12TH AVE S · 98144
Seattle Energy Benchmarking Ordinance (SMC 22.920) · reporting year 2025
Benchmarking record
| Field | Value |
|---|---|
| ENERGY STAR score | 100 (band A) |
| Site EUI | 15.3 kBtu/ft² |
| Source EUI | 42.7 kBtu/ft² |
| GHG emissions | 32 tCO₂e |
| GHG intensity | 0.1 kgCO₂e/ft² |
| Electricity | 1,641,723 kWh |
| Gross floor area | 358,048 sq ft |
| Source record | seattle:50884:2025 |
The disclosure history
Year over year
| Year | Score | Δ | Site EUI | GHG emissions |
|---|---|---|---|---|
| 2025latest | 100 | ±0 | 15.3 kBtu/ft² | 32 tCO₂e |
| 2024 | 100 | 22.2 kBtu/ft² | 194 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
- 209 12TH AVE S
- City
- Seattle
- State
- Washington
- ZIP
- 98144
- Coordinates
- 47.60068, -122.31755
Within ~1 km
Nearby benchmarked buildings
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- Emerson (Prev Modera First Hill)score 100
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Mixed Use Property · 383,914 sq ft
See also: most efficient in Seattle · biggest emitters
Frequently asked questions
What is Mason & Main Building A's energy grade?
Mason & Main Building A 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 Mason & Main Building A use?
Its 2025 site energy-use intensity was 15.3 kBtu/ft² (42.7 kBtu/ft² source) across 358,048 sq ft, including 1,641,723 kWh of electricity.
What are Mason & Main Building A's carbon emissions?
Mason & Main Building A reported 32 tCO₂e of greenhouse-gas emissions (0.1 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.
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Dataset updated . Source: Building Energy Benchmarking disclosure, record seattle:50884:2025.