Methodology · Last updated 2026-10-05 · Primary sources only

How we compute the numbers.

NYC results are preliminary estimates from available public records and supported DOB rules. Review the matching building identity, energy year, property-use allocation and modeled year. The lookup does not certify owner disclosures or determine final filing liability.

Data sources NYC LL97 Boston BERDO Denver Energize Confidence levels PE/RA boundary Update log

Core principle

The current NYC calculation converts each disclosed fuel stream using the modeled year’s factors and sums separate ESPM property-use area limits. Aggregate benchmarking GHG alone is insufficient for this calculation. A source match verifies agreement with the disclosure, not its physical accuracy or eligibility for adjustments.

Section 1

Data sources.

NYC · Local Law 97

Energy consumption (kWh, therms)Matched CY2024 LL84 disclosures via NYC Open Data

Gross floor area (GFA)LL84 source-matched profile area; disclosed use areas determine the ESPM cap

Property type / occupancyExact disclosed ESPM property uses; primary occupancy is peer context only

HVAC permitsNYC DOB permit filings (5-year window)

LL87 energy audit/retro-commissioningNYC DOB LL87 compliance records

Update cadenceSource dates and energy years are shown per record; refreshed inputs require reconciliation.

Boston · BERDO 2.0

Benchmarking dataCity of Boston ISD / ENERGY STAR Portfolio Manager

Emissions limitsBERDO 2.0 regulations (ISD, effective 2024)

Update cadenceAnnual · reviewed every 5 years by Boston Review Board

Denver · Energize Denver

Benchmarking dataDenver Open Data / ENERGY STAR Portfolio Manager

Performance targetsEnergize Denver ordinance (DRMC §4-50)

Update cadenceAnnual · targets through 2032

Section 2

NYC Local Law 97.

ESPM use-area screening. DOB requires ESPM property types from 2026. The October 2026 release models 2026 with CY2024 consumption. The 2030 comparison holds consumption constant, changes electricity and steam factors, and applies 2030–2034 use-area limits. It predicts neither future consumption nor certified compliance.

A calculation requires one reconciled building identity and whole-property disclosure. Missing fuels, conflicting boundaries, unsupported uses, inconsistent allocations and implausible inputs can hold a result without a dollar amount. Coverage and pathway applicability are checked separately. Deductions, credits and approved adjustments are not included. Historical occupancy-based screens remain labeled as legacy methods.

Selected fuel factors used by the current calculator

Energy type	2024–2029 factor	2030 factor	Unit
Electricity	0.000288962	0.000145	tCO₂e / kWh
Natural gas	0.005311	0.005311	tCO₂e / therm
District steam	0.00004493	0.0000432	tCO₂e / kBtu

These 2024–2029 factors apply to modeled 2026; the consumption data year is separate. Additional supported fuels appear in the building’s calculation. Factors and limits: 1 RCNY §103-14.

Selected ESPM property-use intensity limits

Disclosed use	2026 limit	2030–2034 limit
Office	0.00758	0.002690852
Multifamily Housing	0.00675	0.00334664
Data Center	0.02381	0.014791131
Worship Facility	0.00574	0.001230602

Limits are metric tons CO₂e per square foot per year, copied directly from 1 RCNY §103-14(c)(3)(i) and (iii). No ×1,000 scaling applies: 100,000 SF of Office in 2030 gives 100,000 × 0.002690852 = 269.0852 tCO₂e/year. Multiply each disclosed use area by its corresponding limit, then sum. These examples are not a complete category list.

Penalty formula

Actual emissions= Σ (disclosed fuel quantity × modeled-year factor)

Emissions cap= Σ (disclosed use area × ESPM use limit for modeled year)

Excess= max(0, actual_emissions − emissions_cap)

Annual penalty= excess_tCO₂e × $268 / tCO₂e

$268/tCO₂e is the basic excess-emissions rate in DOB’s Article 320 violations guidance. Filing obligations and mitigation require separate review.

Section 3

Boston BERDO 2.0.

The Building Energy Reporting and Disclosure Ordinance requires covered buildings to meet annual emissions standards starting in 2025 (≥35,000 SF) and 2030 (20,000–35,000 SF). The penalty for non-compliance is the Alternative Compliance Payment (ACP).

ACP rate: $234 / tCO₂e above the emissions limit. The rate is reviewed and may be reset by the Boston Review Board every 5 years. Source: BERDO 2.0 implementing regulations (ISD), effective 2024.

Penalty formula

Excess emissions= max(0, actual_tCO₂e − BERDO_limit_tCO₂e)

Annual ACP= excess_tCO₂e × $234

Section 4

Denver Energize Denver.

Energize Denver (DRMC §4-50) sets building energy performance targets through 2032. Penalties are assessed per kBtu of shortfall below the target, with rates tiered by which compliance timeline the building is on.

Compliance timeline	Penalty rate	Maintenance rate
Standard	$0.42 / kBtu shortfall	$0.23 / kBtu
Extended	$0.63 / kBtu shortfall	$0.35 / kBtu
Original	$0.30 / kBtu shortfall	$0.15 / kBtu

Buildings that never benchmarked are subject to an additional $10 / SF penalty. Penalties compound annually until the building meets its performance target.

Penalty formula

kBtu shortfall= max(0, actual_kBtu/SF − target_kBtu/SF) × GFA_SF

Annual penalty= kBtu_shortfall × rate[timeline]

Section 5

Confidence levels.

Confidence describes the available inputs and supported calculation. It does not certify a disclosure, prove compliance or approve a filing. Confirm the applicable professional review and reporting requirements separately.

HIGH

Current NYC ESPM: building identity, energy year, all fuel streams and area match a reconciled disclosure; use areas reconcile and the calculation passes publication checks. Original reporting errors and unmodeled adjustments remain possible.

MEDIUM

Historical methods may use aggregate GHG and assumptions about the fuel mix. This is not the current ESPM calculation. A uniform electricity-factor ratio does not validate mixed-fuel emissions or a building’s penalty.

LOW

Current inputs cannot support a published estimate, or require source review. No dollar amount is shown. A held record may retain verified public context, such as a dated tax-lot grade, without establishing a building’s filing status.

Section 6

What requires a licensed PE or RA.

BuildingFi computes penalty estimates from public data. These estimates are not official compliance determinations and cannot be filed with the city as-is. Confirm the applicable professional review, certification and permitting requirements:

Official emissions report certification — the annual LL97 report requires the certification applicable to the building’s DOB pathway and review of utility inputs and site conditions.

Retrofit scope sign-off — confirm the design, permit and professional sign-off requirements for proposed equipment work; they depend on its scope.

Adjusted baseline disputes — if a building qualifies for an adjusted baseline (e.g., data center load, 24/7 operations), the adjustment application requires PE certification of the submitted energy data.

LL87 energy audit / retro-commissioning — separate from LL97 compliance but required for most covered buildings on a 10-year cycle.

BuildingFi shows public records, supported screening calculations, and their limitations. Confirm filing requirements with official records and a qualified professional.

Section 7

Update log.

2026-10-05

NYC screening now uses reconciled LL84 source inputs, separately allocated ESPM use-area limits and modeled-year fuel factors. Unsupported and inconsistent inputs are held without dollar estimates. The source year, modeled year and tax-lot grade year remain distinct.

2026-06-09

Initial methodology publication. NYC LL97 factors confirmed against Admin Code §28-320.3.4 Table 320-3 (primary source). Boston BERDO ACP confirmed at $234/tCO₂e from ISD implementing regulations. Denver Energize tiered rates confirmed from DRMC §4-50 text: Standard $0.42, Extended $0.63, Original $0.30 per kBtu shortfall. The initial electricity-factor comparison has been superseded by the October update. A ratio of electricity factors is not a universal correction to a penalty; the full calculation depends on fuel totals, use areas, and the modeled year.

This page is updated when statutory factors or penalty rates change. Changes are logged here with effective dates. The Boston and Denver reference sections were last reviewed on June 9, 2026; this update validates the NYC calculation.

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