Methodology · Last updated 2026-06-09 · Primary sources only

How we compute the numbers.

Every penalty figure on BuildingFi is computed from the statute — not from benchmarking program GHG totals, not from averages, not from estimates. Here's the exact arithmetic.

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

Core principle

Local compliance law penalties always use their own emission factors. Never feed a benchmarking program's reported GHG directly into a penalty formula. National benchmarking programs (ENERGY STAR Portfolio Manager) use national or regional eGRID factors. Local compliance laws use their own factors, set in the law text. These can differ by 20–50% for electricity in low-carbon grids.

Section 1

Data sources.

NYC · Local Law 97

Energy consumption (kWh, therms)LL84 annual benchmarking filings via NYC Open Data

Gross floor area (GFA)NYC PLUTO (Dept. of Finance) → CBL → LL84 self-reported

Property type / occupancyPLUTO land use code → LL97 occupancy group mapping

HVAC permitsNYC DOB permit filings (5-year window)

LL87 energy audit/retro-commissioningNYC DOB LL87 compliance records

Update cadenceLL84 filings: annual (May deadline). PLUTO: quarterly.

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.

The 1.41× correction. LL84 / ENERGY STAR uses ~0.000408 tCO₂e/kWh for NYC electricity (national eGRID factor). LL97 Table 320-3 uses 0.000288962 tCO₂e/kWh — the statutory factor. Feeding LL84's reported total GHG directly into the LL97 penalty formula overstates penalties for electric-heavy buildings by approximately 1.41×. We compute from raw kWh × the statute factor, not from the LL84 total.

Emission factors — Admin Code §28-320.3.4, Table 320-3

Energy type	Factor	Unit	Derivation
Electricity	0.000288962	tCO₂e / kWh	Table 320-3
Natural gas	0.005311	tCO₂e / therm	53.1 kgCO₂e/MMBtu × 0.1 MMBtu/therm
Steam	0.04493	tCO₂e / Mlb	Table 320-3
Fuel oil #2	0.01026	tCO₂e / gallon	Table 320-3
Fuel oil #4	0.01080	tCO₂e / gallon	Table 320-3
Fuel oil #6	0.01138	tCO₂e / gallon	Table 320-3
Diesel	0.01026	tCO₂e / gallon	Table 320-3

Occupancy group intensity limits — §28-320.3.1 / §28-320.3.2

Group	Approx. use types	2024–2029 limit	2030–2034 limit
A	Assembly, worship	0.01074	0.00420
B	Office, business	0.00846	0.00453
E / I-4	Schools, education	0.00758	0.00344
I-1	Assisted living, senior care	0.01138	0.00598
F	Factory, industrial	0.00574	0.00167
HIGH_INTENSITY	Hospital, medical, laboratory	0.02381	0.01330
M	Retail, mercantile, restaurant	0.01181	0.00403
R-1	Hotel, motel, lodging	0.00987	0.00526
R-2	Multifamily residential	0.00675	0.00407
S / U	Warehouse, storage	0.00426	0.00110

Units: tCO₂e / SF / year. Source: NYC Admin Code §28-320.3.1–3.2.

Penalty formula

Actual emissions= Σ (energy_quantity × Table_320_3_factor)

Emissions cap= intensity_limit[occupancy_group][period] × gross_floor_area_SF

Excess= max(0, actual_emissions − emissions_cap)

Annual penalty= excess_tCO₂e × $268 / tCO₂e

$268/tCO₂e is the statutory rate (Admin Code §28-320.3.3). This rate does not index to inflation.

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.

Every building record carries a confidence level that reflects how directly the penalty was computed. High-confidence figures are suitable for preliminary planning; all figures require PE/RA certification before official filing.

HIGH

Raw kWh and therms available from the LL84 filing. Penalty computed directly: kWh × 0.000288962 + therms × 0.005311. No dependence on benchmarking GHG totals. Most reliable; error risk limited to data entry in the original LL84 filing.

MEDIUM

Total GHG from LL84 is available and corrected using the ratio of Table 320-3 to the eGRID factor (÷ 0.000408 × 0.000288962 ≈ ÷ 1.41 for electricity-heavy buildings). Accuracy depends on the accuracy of the LL84 total and the fuel mix assumption. Use for directional planning only.

LOW

Insufficient energy data to compute a reliable figure. Building page is marked noindex and penalty is shown as "—". The record is still accessible via direct link for QR/direct-mail use cases.

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. A licensed Professional Engineer (PE) or Registered Architect (RA) is required for:

Official emissions report certification — the annual LL97 report submitted to DOB must be certified by a PE or RA who has reviewed the underlying utility data and site conditions.

Retrofit scope sign-off — any mechanical work (HVAC replacement, chiller, boiler) requires a PE-stamped set of drawings filed with DOB.

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's role: compute from public data, show the math, and connect you with an engineer who already knows your numbers — no duplicate intake.

Section 7

Update log.

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. 1.41× correction documented as the ratio of eGRID (0.000408) to Table 320-3 (0.000288962) electricity factors.

This page is updated when statutory factors or penalty rates change. Changes are logged here with effective dates. All factors linked to primary sources above.

See it applied to your building.

Every building record on BuildingFi uses this methodology — and shows the calc tape.

Check a NYC building →Energy cost tracker →