The Limits of Building-Level Urban Heat Attribution: Evidence from LEED-Certified Buildings in Philadelphia

Green building certification systems, such as Leadership in Energy and Environmental Design (LEED), are often assumed to make cities cooler, yet LEED verifies heat-island measures at the design stage and does not measure the temperature of certified buildings. This study examines whether the certification, the physical interventions around certified buildings, or their location explains summer land-surface temperature (LST) in Philadelphia, a densely built city with a humid subtropical climate. For 641 LEED-certified parcels, canopy, impervious cover, roof albedo, and LST are measured from a high-resolution land-cover raster and multi-date Landsat imagery, and each parcel is compared with matched non-certified parcels nearby. The certification level explains less than 2% of the variation in LST, and LEED parcels are not measurably cooler than their neighbors (−0.18 °C; 95% confidence interval −0.41 to 0.09 °C). The imagery-derived variables explain about nine times as much variation as certification, and neighborhood canopy and roof albedo remain associated with lower LST once strong spatial autocorrelation (Moran’s I = 0.76) is modeled. Under spatially blocked cross-validation, however, the building and parcel features have no predictive skill, whereas location alone predicts LST with an R2 of 0.83. Cooling becomes measurable once canopy within 90 m exceeds about 12%. Surface temperature around LEED buildings therefore reflects their location far more than their certification, and heat benefits appear more likely to come from neighborhood-scale greening than from certifying individual buildings.