Fire alarm design in Singapore means deciding where detectors and manual call points go, how the building is split into zones, how devices are wired back to the panel on loops, and what every alarm signal must trigger. That last part is written down in a cause-and-effect matrix. The design is prepared to SS 645, with BS 5839 where the specification calls for it, and to the SCDF Fire Code, then packaged as drawings for the SCDF submission. Good fire alarm design services get four things right: the detection suits each room's use, the zones make sense to a firefighter, the loops are resilient, and the interfaces with other systems are complete. This guide walks through each one. In Singapore, fire alarm systems are designed to SS 645, the code of practice that replaced SS CP 10 in 2019 and that the SCDF Fire Code requires.
Codes in this area are revised and superseded. Before you start, confirm which code and edition apply to your project, and design to that edition. Do not carry spacing, coverage or other values over from an old job.
What a fire alarm design has to deliver
A complete design answers five questions:
- What is the system category? The level of protection the building needs, set by the fire safety requirements and the code.
- Where are the detectors and call points? The right detector type for each room, placed to the code's spacing and coverage rules.
- How is the building zoned? Zones that let the fire brigade find the fire quickly from the panel.
- How are devices connected? Loop layout, isolators and panel locations that keep the system working if a cable is damaged.
- What happens when it alarms? Every output the system must drive, recorded in a cause-and-effect matrix.
Inputs to confirm before you design
Most redesign comes from starting before these are settled:
- Architectural plans, sections and reflected ceiling plans for every area
- Ceiling heights, ceiling types and any voids that need protection
- The use of each room, including kitchens, plant rooms and stores
- Fire safety requirements or consultant comments already issued
- The code and edition the project is designed to
- Compartment and fire escape layout
- The list of interfacing systems: sprinklers, gas suppression, ACMV, smoke control, lifts, access control, public address
- The panel or system type, if already chosen by the specification
- Submission format: AutoCAD or Revit, title blocks and drawing list
The design process, step by step
- Confirm the system category and code. Take them from the fire safety requirements and the project specification. Record the code edition on the drawings.
- Choose the detector type for each room. Match the detector to the expected fire and to normal conditions in the room. Areas with steam, dust or cooking fumes need a type that will not cause false alarms.
- Lay out detectors. Apply the code's spacing and coverage rules for the detector type and ceiling. Check beams, ceiling voids, raised floors and changes in ceiling height, which often need extra devices.
- Place manual call points. Locate them on escape routes and at exits as the code requires, so they are found without searching.
- Place sounders and visual alarms. Make sure the alarm is heard, or seen where required, in every area the code requires, including enclosed rooms such as plant rooms that are easy to overlook.
- Define the zones. Follow fire compartments and floor boundaries. Keep each zone to an area a firefighter can search quickly, within the limits the code sets.
- Design the loops. Route addressable loops so that isolators limit the effect of a single fault. Show device addresses and isolator positions on the drawings.
- Locate the panels. Put the main panel and any repeaters where the fire brigade will arrive, as the fire safety requirements direct.
- Write the cause-and-effect matrix. List every input against every output, including delays and staged alarms if the design uses them.
- Coordinate interfaces. Agree interface points and signal types with the ACMV, lift, sprinkler, gas suppression and security trades.
- Package for submission. Produce floor plans, a riser or schematic diagram, the zone chart, the matrix and legends in the Singapore submission format.
Conventional or addressable
A conventional system reports alarms by zone. An addressable system identifies each device, which makes fault finding faster and the cause-and-effect matrix more precise. The specification normally sets which one you use. If it does not, raise it as a tender query rather than assuming.
What goes into a cause-and-effect matrix
The matrix is the document most likely to be incomplete. A typical layout:
| Input (cause) | Example outputs (effects) | Who confirms the interface |
|---|---|---|
| Smoke or heat detector zone | Sounders, panel indication, ACMV shutdown for the area | ACMV contractor |
| Manual call point | Sounders, alarm signal to the monitoring service | Fire alarm contractor |
| Sprinkler flow switch | Zone alarm, sounders, pump status indication | Sprinkler contractor |
| Gas suppression panel | Pre-discharge alarm, ACMV and damper shutdown, door release | Gas suppression contractor |
| Any fire alarm | Lift homing, access control release, smoke control start | Lift, security and ACMV contractors |
The exact effects come from the fire safety requirements and the code for your project. The table shows the structure, not a template to copy.
What a submission-ready package contains
- A design basis sheet: code and edition, system category, panel type and design notes
- Floor plans with detectors, call points, sounders, visual alarms and device addresses
- Zone boundaries and a zone chart matching the panel
- A riser or schematic diagram showing loops, isolators, panels and repeaters
- The cause-and-effect matrix
- Interface details for other systems
- Legends and symbols consistent across every sheet
Drawings, zone chart and matrix must agree. If a zone changes late, update all three. Where PE endorsement is required, the PE reviews the whole package, so consistency saves a review cycle.
Common mistakes
- Using values from an old project. Spacing and coverage depend on detector type, ceiling and code edition. Take them from the code each time.
- Ignoring ceiling voids and raised floors. Concealed spaces are easy to miss on a plan and are often picked up at review.
- Wrong detector in the wrong room. Smoke detectors near kitchens or steam sources cause false alarms that erode trust in the system.
- Zones that do not follow compartments. A zone crossing a compartment or floor boundary sends firefighters to the wrong place.
- An incomplete matrix. Interfaces agreed in meetings but never written into the matrix get missed at testing.
- Late coordination with other trades. ACMV, lift and security interfaces need agreed signal types early, not during commissioning.
- Drawings and matrix out of step. Every change must be reflected in the plans, zone chart and matrix together.
Related guides
For the sprinkler side of the same submission, see sprinkler hydraulic calculations. When the project reaches handover, see as-built drawings and MEP handover.
How Newham can help
Newham's fire protection engineers prepare fire alarm design to SS 645, with BS 5839 where the project specification calls for it: detection layout, zoning, loop design and cause-and-effect matrices, formatted for SCDF submission in AutoCAD or Revit. Where a submission needs Professional Engineer endorsement, we coordinate review by a Singapore-registered PE and quote those fees separately. Work is priced per deliverable or on a monthly retainer, billed in SGD, with the scope confirmed in writing first. See fire protection design, or book a discovery call to scope your next package.