Disclaimer & Methodology

Data Sources

CompliantLens derives its compliance estimates from publicly available datasets published by the City of New York through the NYC Open Data portal (Socrata/SODA API):

• LL84 Energy Benchmarking — Annual energy and water consumption data self-reported by building owners as required by Local Law 84
• PLUTO (Primary Land Use Tax Lot Output) — Property characteristics including building class, floor area, zoning, and ownership from the NYC Department of City Planning
• DOB Job Application Filings — Department of Buildings permit records filtered for energy-related retrofit activity

LL84 Data Limitations

LL84 benchmarking data is self-reported by building owners and property managers. The City of New York does not independently audit or verify the accuracy of these submissions. Known limitations include:

• Data may be incomplete for buildings with mixed or unusual energy sources
• Reported values may contain entry errors or use inconsistent measurement methods
• Data publication schedules mean figures may lag by 6–18 months
• Not all subject buildings have filed benchmarking reports in every year

Carbon Coefficients

CompliantLens calculates building emissions using the carbon coefficients specified in Local Law 97 (NYC Administrative Code §28-320.3.1.2):

• Electricity: 0.000288962 tCO2e/kBtu
• Natural Gas: 0.00005311 tCO2e/kBtu
• District Steam: 0.00004493 tCO2e/kBtu
• Fuel Oil #2: 0.00007421 tCO2e/kBtu
• Fuel Oil #4: 0.00007529 tCO2e/kBtu

These coefficients may be updated by the City of New York as the grid decarbonizes. CompliantLens uses the most recently published values at the time of calculation.

Penalty Calculation

LL97 imposes a penalty of $268 per metric ton of CO2 equivalent (tCO2e) exceeding a building's annual emission limit. Limits vary by property type and compliance period:

• 2024–2029: First compliance period with higher emission limits
• 2030–2034: Second compliance period with stricter limits

Our penalty estimates do not account for allowable deductions such as Renewable Energy Credits (RECs), clean energy electrification offsets, or approved adjustment applications, all of which can reduce or eliminate actual penalties.

Emission Limits & Methodology

We estimate a building's annual emissions limit using the Energy Star Portfolio Manager (ESPM) property-type emission factors (tCO2e per square foot) published by the NYC Department of Buildings in 1 RCNY §103-14: subparagraph (i) for the 2024–2029 period and subparagraph (iii) for 2030–2034. This is the methodology DOB requires for official building emissions reports, mandatory for all covered buildings from calendar year 2026. We look up the factor for each benchmarked property use type and, for mixed-use buildings, blend the factors by floor area. These factors are transcribed directly from the rule and pinned by automated tests.

Where a benchmarked use type has no assignable ESPM factor - for example “Mixed Use Property,” “Other,” or an unrecognized value - we fall back to the occupancy-group factors in NYC Administrative Code §28-320.3.1/§28-320.3.2 as a conservative estimate, and each building's compliance card shows which basis was used.

This is still an estimate, not an official determination. The actual limit and any penalty are set by NYC DOB from a report prepared by a registered design professional. Their figure can differ from ours because of inputs we cannot see - the exact ESPM property-type classification of each space, the floor-area split between uses, and allowable deductions such as Renewable Energy Credits, clean-energy electrification offsets, or approved adjustment applications, none of which are modeled here. Verify with a qualified professional before acting.

Retrofit Estimates

Retrofit cost and savings estimates displayed on CompliantLens are based on industry averages from published sources including ASHRAE, DOE, and NYSERDA reference data. They are not site-specific engineering quotes and may differ significantly from actual project costs due to building conditions, contractor pricing, permitting requirements, and market conditions.

Not a Substitute For

CompliantLens estimates are not a substitute for:

• An official LL97 compliance filing with the NYC Department of Buildings
• An ASHRAE Level II or Level III energy audit
• A professional engineering study or retro-commissioning assessment
• Legal advice regarding compliance obligations or penalty disputes
• Financial advice regarding capital expenditure planning

Always consult qualified professionals — licensed energy engineers, attorneys, and certified public accountants — before making compliance or investment decisions based on the information provided by CompliantLens.

Contact

If you have questions about our methodology or data sources, contact us at [email protected].