Aegis Living Lake Union

How does Aegis Living Lake Union compare with other senior living community buildings in Seattle?

The latest disclosures cover 48 senior living community buildings in Seattle, out of 3,871 buildings citywide. Aegis Living Lake Union's ENERGY STAR score of 77 compares with an average of 72 across the 40 that report a score; it scores higher than 43% of them and lower than 55%. Its site EUI of 47.9 kBtu/ft² is about 28% below the average of 66.7 kBtu/ft² — it uses less energy per square foot than the typical building in that group. Its emissions intensity of 0.3 kgCO₂e/ft² is about 84% below the group average of 1.7 kgCO₂e/ft².

At 73,322 sq ft, it is about half of the average floor area of 136,458 sq ft for those buildings. It was built in 2021, 30 years later than the group's average year built (1991). Across all 24 jurisdictions BuildingCensus covers, the 1,181 senior living community buildings average an ENERGY STAR score of 71 and a site EUI of 73.6 kBtu/ft².

How has Aegis Living Lake Union's energy performance changed over time?

BuildingCensus holds 3 Seattle disclosures for Aegis Living Lake Union, covering report years 2023–2025. Site EUI moved from 50.7 kBtu/ft² (2024) to 47.9 kBtu/ft² (2025), a 6% decrease. Reported emissions went from 18 tCO₂e to 17 tCO₂e over the same span (down 6%).

What does an ENERGY STAR score of 77 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 77 means the building performs better than about 77% of its national peers. BuildingCensus bands the score into report-card grades; 77 falls in band B — above median (70–84). 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. Aegis Living Lake Union's 47.9 kBtu/ft² across 73,322 sq ft works out to about 3.5 billion Btu (1,029 MWh-equivalent) in 2025. Its source EUI of 134.1 kBtu/ft² also counts the energy lost generating and delivering that power, which is why it is higher. The disclosure also reports 839,510 kWh of electricity for the year.

Which law requires Aegis Living Lake Union to report its energy use?

Aegis Living Lake Union 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:50918:2025). 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.