If you've been in the NYC fire alarm business long enough, you know the question that comes up on nearly every existing building job: "Does this require new plans or not?" The answer has always depended on whether the work is classified as a Repair, an Alteration, or something that triggers full system replacement. The problem is that the line between those three categories was never clean — until Buildings Bulletin 2024-001 was issued on February 9, 2024.
BB 2024-001, issued by DOB Assistant Commissioner Joseph Ackroyd, P.E., CFM, supersedes BB 2015-025 and provides the most detailed and authoritative guidance to date on how to classify work on existing fire alarm systems approved under the 2014 Building Code or prior codes, now subject to the 2022 Construction Codes. This is the document you need to know cold before writing a scope of work on any existing building job in NYC.
SCOPE OF THIS BULLETIN
BB 2024-001 applies to existing approved fire alarm systems installed under the 2014, 2008 Building Code, or Prior Codes. It does not apply to new construction. The relevant code sections are AC 28-101.4.3, BC 901.9, BC 907, BC 915, and the current NYC Electrical Code. Source: BB 2024-001 Official PDF ↗
The Three-Tier Framework: Repair, Alteration, Replacement
BB 2024-001 organizes all fire alarm work in existing buildings into three distinct tiers, each with different filing requirements and compliance obligations:
TIER 1 — REPAIR
No new plans required. No FDNY filing. Work performed by a licensed electrician. System functionality must not change. In-kind replacement only, same manner and arrangement as existing.
TIER 2 — ALTERATION
New plans must be filed and approved by FDNY. Five specific alteration types are defined. Full system replacement is NOT required. Specific conditions apply to each type.
TIER 3 — FULL SYSTEM REPLACEMENT
New permit application required. Entire system replaced to comply with current 2022 NYC Construction Codes. Triggered when repair and alteration conditions cannot be met, or when parts are unavailable.
Tier 1 — What Counts as a Repair
Section II of BB 2024-001 defines Repair by reference to BC 901.9.1.1. The key test: does the work change the system's functionality? If no, and if the work is in-kind and in the same arrangement as the existing approved installation, it's a Repair.
Specific examples the Bulletin explicitly classifies as Repair:
- Repair or in-kind replacement of initiating devices — smoke detectors, water flow switches, manual pull stations
- Repair or in-kind replacement of notification appliances — audible and visible devices
- Repair of control panels or distributed control units — including Remote Control Units (RCU), Terminal Transmission Boxes (TTB), and Data Gathering Panels (DGP) — for the purpose of maintaining them in working order
REPAIR ≠ UPGRADE
In-kind means in-kind. Replacing a conventional smoke detector with an addressable one changes the system's functionality and is not a Repair under this Bulletin — it becomes an Alteration requiring FDNY plan filing. The same logic applies to upgrading a notification appliance to a different listed model with different output characteristics.
Tier 2 — The Five Alteration Types
Section III defines the alteration types that require new FDNY plan filing but do not require full system replacement. Understanding these five types — and their specific conditions — is where most filing errors happen.
But first, an ARCS trigger that applies across all alteration types:
ARCS TRIGGERS WITHIN ALTERATIONS — READ THIS FIRST
Even when your work qualifies as a limited-scope Alteration (no full system replacement), ARCS must be newly installed if not already present in three scenarios:
(1) The value of the alteration triggers BC 901.9.4.1
(2) The scope creates a High-Rise Building per 2022 BC 202, or a large-area building per BC 907.2.2.2, 907.2.7.1, or 907.2.10.1
(3) The alteration results in a change of occupancy or use in a high-rise or large-area building per BC 901.9.2 Item 1
FDNY may determine ARCS is not required per BC 916.3. Always confirm with the project's design professional before finalizing scope.
Alteration Type A — Section III.A
Relocation or Replacement of FCC, FCS, FACP, or Distributed Control Units
Replacing or relocating the Fire Command Center, Fire Command Station, Fire Alarm Control Panel, RCU, TTB, or DGP does not require full system replacement — but it requires FDNY plan filing and all four of the following conditions must be met:
- Sequence of operation must match the existing approved system — or be reprogrammed per NFPA 72 as amended by 2022 BC Appendix Q, as if for new construction of similar building characteristics
- Existing wiring may be reused if power capacity is adequate — but splicing of existing non-power-limited fire alarm system wiring is prohibited
- If existing power capacity is not adequate, a new non-power-limited wiring connection compliant with Article 760 of the NYC Electrical Code is required
- Where equipment is relocated (not just replaced in place), proximity and distance requirements for elevator control panels and mechanical fan control panels must be maintained
The no-splice rule is the one that catches contractors. If you're relocating an FACP and the existing non-power-limited runs are too short to reach the new location, you cannot splice them — you need to run new wiring.
Alteration Type B — Section III.B
Floor Alterations — Full Floor vs. Partial Floor
This is the distinction that determines how much of the floor's existing devices need to be brought up to current code:
- Full-floor alteration: All existing core-related fire alarm devices (per FDNY Bulletin 01-09/2020) AND all newly installed devices required by 2022 BC 907 on that floor must comply with current Construction Codes and NYC Electrical Code
- Partial-floor alteration: Compliance is limited to newly installed devices within the area of the partial alteration only. For the portion of the floor not being altered, existing functional devices and wiring may remain
Where a floor alteration requires initiating devices or notification appliances that cannot be supported by the existing system's control panel, new control panels or distributed control units (RCU, TTB, DGP) may be installed — provided they are installed in a similar manner with wiring comparable to the existing approved installation.
Alteration Type C — Section III.C
System Technology Upgrade
This is the most technically complex alteration type — and the one with the most conditions. A system technology upgrade covers the replacement or upgrade of control panels, distributed control units, FCC, FCS, or FACP where the scope goes beyond in-kind repair.
Location: New or upgraded control panels and distributed control units must be installed in the same room or location as the existing equipment.
Riser wiring: Fire alarm system wiring for the riser portion of the upgrade must comply with the survivability standards in NFPA 72, as amended by 2022 BC Appendix Q.
Power supply: If existing battery power capacity supports all system functions after the upgrade, a new electrical power supply is not required. If existing power is inadequate, a new supply must be provided for all affected equipment per the current NYC Electrical Code and applicable survivability requirements.
Initiating devices:
- Selective coverage smoke detection required by 2022 BC 907.2 items (1) and (2) must be installed throughout the building at code-required locations if not already present
- Existing initiating devices may remain if functional
- If all initiating devices are replaced as part of the upgrade, the installation must comply with 2022 BC
Notification appliances:
- All notification appliance circuits must be supervised upon completion of the upgrade
- If all notification appliances are replaced, the installation must comply with 2022 BC
Sequence of operation must be programmed per 2022 BC as if for new construction of similar building characteristics. Exception: partial evacuation buildings without one-way voice communication that don't fall under item 8 below.
One-way voice communication: A new one-way voice communication system must be installed in accordance with 2022 BC requirements in any existing building with a height greater than 125 feet (measured from the lowest level of FDNY vehicle access to the highest occupied floor) — if a one-way voice system does not currently exist. This is a hard requirement with no exception for cost or feasibility.
TECHNOLOGY UPGRADE: THE DCU REQUIREMENT
A system technology upgrade under Section III.C applies specifically to systems that have both a distributed control unit (RCU, TTB, or DGP) and a fire alarm control panel. Systems that have only a control unit — without a separate FACP — do not qualify for the technology upgrade classification under this section. Misidentifying the system type before scoping the job is how projects end up in the wrong alteration category at plan review.
Alteration Type D — Section III.D
Building Enlargements — Same Use and Occupancy
Extending a fire alarm system into an enlarged portion of a building does not require full system replacement — if all six of the following conditions are met simultaneously:
- The extended system must have the same sequence of operation as the existing building's previously approved system
- All portions of the existing system that require modification to support the enlargement must comply with the 2022 NYC Construction Codes
- All enlarged portions must have the same occupancy class as the existing building
- The enlargement must not cause the building to be reclassified as a large-area building per BC 907.2.2.2, 907.2.7.1, or 907.2.10.1
- The existing building cannot be a high-rise, and the enlargement cannot cause the building to be reclassified as one
- Within the enlarged portions, all devices, appliances, and wiring must comply with all 2022 Construction Code requirements
If the enlargement causes a high-rise or large-area building reclassification — the entire building fire alarm system must be replaced. This is a non-negotiable trigger.
Alteration Type E — Section III.E
Change of Occupancy Class in a Space
Where work in any space constitutes a change in the occupancy classification of that space, full system replacement is not required — provided that a fire alarm system per BC 901.9.2 item 2 serves the space with the changed occupancy, and the interface with the existing building-wide fire alarm system is subject to DOB review.
Critical distinction: This only applies to a change in occupancy of a space. If the change is to the main use or dominant occupancy of the entire building, per BC 901.9.2 item 1, a full new building fire alarm system is required — no exceptions.
Quick Reference: What Requires Filing?
| Work Type | FDNY Filing | Full Replacement | Key Condition |
|---|---|---|---|
| In-kind device replacement (smoke detector, pull station, NAC device) | No filing | Not required | Same manner, same arrangement, functionality unchanged |
| Control panel / DCU repair (RCU, TTB, DGP) | No filing | Not required | Maintaining in working order only |
| FACP / FCC relocation or replacement | Required | Not required | No splicing; sequence of operation must match or be reprogrammed per Appendix Q |
| Full-floor alteration | Required | Not required | All core devices + new devices on that floor must comply with 2022 BC |
| Partial-floor alteration | Required | Not required | Compliance limited to altered area only; rest of floor may remain |
| System technology upgrade | Required | Not required | Must have both DCU and FACP; 125 ft voice comm trigger applies |
| Building enlargement (same occupancy) | Required | Only if high-rise/large-area triggered | All 6 conditions must be met simultaneously |
| Change of occupancy in a space | Required | Only if dominant occupancy changes | Space-level change allowed; building-level change = full replacement |
| System cannot be repaired or parts unavailable | Required | Required | Full compliance with 2022 Construction Codes |
Every Alteration Filing Starts with a TM-1
Whether you're filing a panel relocation, a floor alteration, or a technology upgrade, FDNY requires a completed TM-1 as part of the application. Fire PDF Pro pulls live DOB data — correct BIN, building class, construction type, occupancy group — and auto-fills it in seconds.
Auto-Fill Your TM-1 →Frequently Asked Questions
The information in this article is intended for general informational purposes and reflects the content of NYC Buildings Bulletin 2024-001 as published by the NYC Department of Buildings on February 9, 2024. It does not constitute legal, engineering, or professional code compliance advice. Building code requirements, DOB bulletins, and FDNY filing procedures are subject to change and may be interpreted differently based on project-specific conditions. Readers should verify all requirements with current official sources and consult with a licensed New York State professional engineer, registered architect, or qualified expediter before making project decisions. Fire PDF Pro and GLA Enterprise assume no liability for actions taken in reliance on this information.