Two regimes at a glance
| Article 320 | Annual emissions caps from 2024, tightening in 2030 (§28-320.3; 1 RCNY §103-14(c)(3)). Annual May 1 report certified by a design professional (§28-320.3.7). Over the cap: an estimated maximum of $268 per ton over, per year (§28-320.6). |
|---|---|
| Article 321 | No annual cap. A one-time obligation: either complete thirteen prescriptive energy conservation measures (§28-321.2.2) or demonstrate 2024 emissions under the would-be 2030 limit (§28-321.2.1), documented in a one-time report that was due May 1, 2025 (§28-321.3). Penalties are fixed amounts, not per-ton (1 RCNY §103-17). |
The per-ton penalty structurally cannot reach an Article 321 building: the covered-building definition excepts them from Article 320 (§28-320.1), and Article 321's own penalty section was repealed and replaced with rule-level fixed penalties (§28-321.4, repealed by LL147/2019 §18).
Which buildings are Article 321
A covered building falls under Article 321 if any of these apply:
| > 35% rent-regulated | More than 35% of dwelling units are rent-regulated accommodations. Exactly 35% is not more than 35% — the threshold is strict. |
|---|---|
| HDFC co-op | Housing Development Fund Corporation cooperatives. |
| Project-based federal assistance | Buildings with project-based federal assistance such as a HAP contract. Tenant-held Section 8 vouchers do not qualify a building. |
| House of worship | Classified A-3 occupancy houses of worship where more than half the floor area is used for worship. |
Two nearby categories are often mistaken for Article 321 but stay under Article 320 with deferred caps: buildings with more than zero but at most 35% rent-regulated units get caps starting in 2026 (first report May 1, 2027) (§28-320.3.10.1; 1 RCNY §103-14(b)(8)(i)), and Mitchell-Lama buildings that also contain income-restricted units get their first binding limits in 2035–2039 (§28-320.3.9) — the statute requires both prongs, not either.
The two Article 321 routes
An Article 321 building complied in one of two ways, and the one-time report documents which:
Prescriptive route (§28-321.2.2): implement all thirteen prescribed energy conservation measures, fully in place before January 1, 2025. The statutory list, condensed:
- Adjusting temperature set points for heat and hot water
- Repairing all heating system leaks
- Maintaining the heating system
- Installing individual temperature controls or insulated radiator enclosures with temperature controls on all radiators
- Insulating all pipes for heating and hot water
- Insulating the steam system condensate tank or water tank
- Installing indoor and outdoor heating system sensors and boiler controls
- Replacing or repairing all steam traps
- Installing or upgrading master venting at the ends of mains, large horizontal pipes, and tops of risers
- Upgrading lighting to comply with the standards for new systems in NYC Energy Conservation Code §C405
- Weatherization and air sealing (windows, ductwork, whole-building insulation)
- Installing timers on exhaust fans
- Installing radiant barriers behind all radiators
Performance route (§28-321.2.1): demonstrate that calendar-year 2024 emissions came in at or under the limit that would apply in 2030–2034, computed with the 2030 coefficients — effectively proving the building is already ahead of the curve, measure list not required.
The one-time report was due May 1, 2025 (§28-321.3), filed with a $210 DOB fee (1 RCNY §101-03).
Article 321 penalties
Instead of per-ton exposure, the rule sets fixed civil penalties, each assessed per covered building:
| Failure to file | $10,000, attaching 60 days after the deadline or a granted extension (1 RCNY §103-17(d)(1)). |
|---|---|
| Failure to comply | $10,000 (1 RCNY §103-17(e)(1)–(2)). |
| Mitigation | DOB mitigation can reduce either penalty, potentially to zero (1 RCNY §103-17(f)); mediated resolution is an $800 DOB fee on top of the $210 report fee (1 RCNY §101-03; DOB Processing FAQs). |
One more planning fact: under current law there is no sunset — an Article 321 building does not convert to Article 320 annual caps in 2030 or after, contingent on maintaining its qualifying status. Owners planning capital work should still watch the 2030 horizon, but the binding obligation is the one-time report, not an annual reckoning.