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999 Hiawatha Apartments

Multifamily Housing in Seattle, WA · 945 HIAWATHA PL S · 98144

At a glance

999 Hiawatha Apartments is a 122,941-square-foot multifamily housing building at 945 HIAWATHA PL S in Seattle, Washington, built in 2014. In its 2025 Seattle benchmarking disclosure it reported an ENERGY STAR score of 95 out of 100 (grade A), a site energy-use intensity of 32.2 kBtu/ft² and 12 tCO₂e of greenhouse-gas emissions. That score is higher than 61% of the 1,652 scored multifamily housing buildings in Seattle.

ENERGY STAR score
95
band A · 2025
Site EUI
32.2
kBtu/ft²
GHG emissions
12
tCO₂e
GHG intensity
0.2
kgCO₂e/ft²
Floor area
122,941
sq ft
Year built
2014
vintage
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85–10070–8455–691–54
This entry + 6 nearby

Seattle Energy Benchmarking Ordinance (SMC 22.920) · reporting year 2025

Benchmarking record

FieldValue
ENERGY STAR score95 (band A)
Site EUI32.2 kBtu/ft²
Source EUI90.1 kBtu/ft²
GHG emissions12 tCO₂e
GHG intensity0.2 kgCO₂e/ft²
Electricity606,400 kWh
Gross floor area122,941 sq ft
Source recordseattle:49866:2025

The disclosure history

Year over year

YearScoreΔSite EUIGHG emissions
2025latest95+232.2 kBtu/ft²12 tCO₂e
202493-333.3 kBtu/ft²12 tCO₂e
202396-231.9 kBtu/ft²12 tCO₂e
202298±030.7 kBtu/ft²11 tCO₂e
202198+130.2 kBtu/ft²11 tCO₂e
20209729.9 kBtu/ft²11 tCO₂e
2019—17.5 kBtu/ft²11 tCO₂e
201897±032.1 kBtu/ft²11 tCO₂e
201797+333.1 kBtu/ft²12 tCO₂e
201694-133.3 kBtu/ft²12 tCO₂e
20159532.8 kBtu/ft²12 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.

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Ownership

No owning organisation shown. Names of private individuals in the disclosure are not published here.

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Location

Address
945 HIAWATHA PL S
State
Washington
ZIP
98144
Coordinates
47.59316, -122.30843

Within ~1 km

Nearby benchmarked buildings

See also: most efficient in Seattle · biggest emitters

How does 999 Hiawatha Apartments 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. 999 Hiawatha Apartments's ENERGY STAR score of 95 compares with an average of 83 across the 1,652 that report a score; it scores higher than 61% of them and lower than 35%. Its site EUI of 32.2 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 0.2 kgCO₂e/ft² is about 73% below the group average of 0.7 kgCO₂e/ft².

At 122,941 sq ft, it is about 42% above 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 999 Hiawatha Apartments's energy performance changed over time?

BuildingCensus holds 11 Seattle disclosures for 999 Hiawatha Apartments, covering report years 2015–2025. Its ENERGY STAR score was 95 in both 2015 and 2025. Site EUI moved from 32.8 kBtu/ft² (2015) to 32.2 kBtu/ft² (2025), a 2% decrease. Reported emissions went from 12 tCO₂e to 12 tCO₂e over the same span (up 4%).

What does an ENERGY STAR score of 95 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 95 means the building performs better than about 95% of its national peers. BuildingCensus bands the score into report-card grades; 95 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. 999 Hiawatha Apartments's 32.2 kBtu/ft² across 122,941 sq ft works out to about 4 billion Btu (1,160 MWh-equivalent) in 2025. Its source EUI of 90.1 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 606,400 kWh of electricity for the year.

Which law requires 999 Hiawatha Apartments to report its energy use?

999 Hiawatha Apartments 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:49866:2025). 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

Frequently asked questions

What is 999 Hiawatha Apartments's energy grade?

999 Hiawatha Apartments scores 95 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 999 Hiawatha Apartments use?

Its 2025 site energy-use intensity was 32.2 kBtu/ft² (90.1 kBtu/ft² source) across 122,941 sq ft, including 606,400 kWh of electricity.

What are 999 Hiawatha Apartments's carbon emissions?

999 Hiawatha Apartments reported 12 tCO₂e of greenhouse-gas emissions (0.2 kgCO₂e/ft²) for 2025.

Where is 999 Hiawatha Apartments?

999 Hiawatha Apartments is at 945 HIAWATHA PL S, in Seattle, Washington 98144. Its coordinates are 47.59316, -122.30843 (latitude, longitude), as published in the Building Energy Benchmarking file.

How big is 999 Hiawatha Apartments and when was it built?

999 Hiawatha Apartments has 122,941 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 999 Hiawatha Apartments 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, “999 Hiawatha Apartments, Seattle, Washington — 2025 benchmarking disclosure”, https://buildingcensus.com/buildings/seattle/999-hiawatha-apartments-c23be906 (data as of October 2, 2026).