Cart is emptyA single-zone smoke control panel manages one smoke ventilation zone — typically one stairwell or corridor — and activates all connected vents and actuators simultaneously on alarm. A multi-zone panel manages two or more independent zones, allowing targeted activation of only the affected area. The choice depends on the number of separate smoke ventilation zones in the building’s fire strategy.
What Is a Smoke Ventilation Zone?
A smoke ventilation zone is a defined area of a building that is treated as a single unit for the purposes of AOV control. When smoke is detected within the zone, the panel activates all vents and dampers within that zone to clear the escape route. A zone might be a single stairwell, a single floor’s lobby, or an entire corridor on one level.
The fire strategy document prepared by the fire engineer defines how the building is divided into zones. In simple buildings — a single-stair block with one corridor per floor feeding a shared stair — a single zone may cover the entire system. In complex buildings with multiple stairwells or independent lobby systems per floor, each area may be a separate zone.
Single-Zone Panels: When to Use Them
A single-zone panel is appropriate when:
- The building has one stairwell and one corridor run serving all floors
- The fire strategy treats the entire common area as one smoke ventilation zone
- All vents and dampers should open simultaneously on any alarm
- Budget and simplicity are priorities and the installation does not require zone isolation for maintenance
Single-zone panels are common in smaller residential blocks — four to twelve storeys, single stair — where the AOV system consists of a vent at the head of the stair, a vent or damper at each lobby, and a single set of detectors covering the common area.
Multi-Zone Panels: When to Use Them
A multi-zone panel is required when:
- The building has more than one stairwell, each with its own independent AOV system
- The fire strategy requires that only the affected zone activates on alarm — not the whole building
- Floors have independent lobby AOV systems that should not all open simultaneously
- Zone isolation is needed for maintenance without taking the entire system offline
- The building’s fire alarm system sends zone-specific signals that the AOV panel must respond to individually
Multi-zone panels are standard in larger residential blocks, hotels, offices, and mixed-use buildings where the fire strategy divides the building into independently managed smoke ventilation areas.
Key Differences at a Glance
| Feature | Single-Zone Panel | Multi-Zone Panel |
|---|---|---|
| Number of zones managed | 1 | 2 or more |
| Activation behaviour | All vents open on any alarm | Only affected zone opens |
| Zone isolation for maintenance | No (whole system offline) | Yes (zone by zone) |
| Complexity | Simple | More complex |
| Typical applications | Small-medium single-stair blocks | Large blocks, multi-stair buildings |
| Cost | Lower | Higher |
Can You Upgrade from Single to Multi-Zone?
In most cases, upgrading a single-zone panel to multi-zone requires replacing the panel entirely. The wiring infrastructure — detector circuits, actuator runs — may be reusable, but the control logic of a single-zone panel cannot be field-upgraded to support independent zone management. If there is any possibility that the building’s fire strategy will evolve (for example if additional zones will be added during phased development), specifying a multi-zone panel from the outset is advisable.
Which Panel Does BS 9991 Require?
BS 9991 does not mandate a specific panel type — it requires that the smoke ventilation system operates in accordance with the fire strategy. If the fire strategy requires zoned activation, a multi-zone panel is required to deliver it. If the fire strategy permits whole-system activation, a single-zone panel may suffice. The fire engineer’s specification is the deciding document.
AOV Direct’s Panel Range
AOV Direct supplies O-Range smoke control panels in both single-zone and multi-zone configurations, compatible with standard 24 V DC AOV actuators and conventional smoke detection circuits. View the full controls range or contact us to discuss your installation requirements.
Frequently Asked Questions
Can a single-zone panel serve multiple floors?
Yes — a single-zone panel can control actuators on multiple floors as long as they all form part of the same smoke ventilation zone. For example, a panel controlling a stairwell vent and lobby vents on each of six floors, where all vents open simultaneously on any alarm, is a single-zone installation despite the physical spread of the equipment.
How do I find out how many zones my building needs?
The number of zones is defined in the building’s fire strategy document, which should have been prepared by a fire engineer. If you are retrofitting an AOV system to an existing building, a fire risk assessor or fire engineer will need to prepare or review the fire strategy before the system can be specified.
Does a multi-zone panel cost significantly more?
Multi-zone panels carry a price premium over equivalent single-zone units, but the difference is modest relative to the overall cost of an AOV installation. For buildings where zoned operation is required under the fire strategy, specifying the correct panel type is not optional — the additional cost is unavoidable.