A dry riser (dry rising main) is an empty pipe that firefighters charge from a pumping appliance through a breeching inlet at ground level. A wet riser is kept full of water and supplied by its own tank and pumps. In Singapore, the SCDF Fire Code 2023 decides which one a building needs, mainly by habitable height: dry rising mains above 10 m and up to 60 m, wet rising mains above 60 m, and dry rising mains in every basement. Systems are installed to SS 575. This guide sets out the main clause 6.2 requirements as of October 2026.
The figures below come from the Fire Code 2023 and its explanatory notes as published by SCDF in October 2026. The Code is amended from time to time, so check the current clause and any circulars before you design. This guide is general information, not a substitute for the QP's design.
Dry or wet: which does the building need?
| Situation | Requirement (Fire Code 2023, cl. 6.2.1) |
|---|---|
| Purpose Groups II–VIII, habitable height over 10 m and up to 60 m | Dry rising main |
| Habitable height over 60 m | Wet rising main |
| Tower over 60 m on a lower podium | Wet rising main for the tower; the podium can be served by a dry rising main |
| Any basement, single or multi-level (not Purpose Group I) | Dry rising main to SS 575, regardless of depth |
| Habitable height 10 m or less | Normally none; SCDF's notes recommend an internal rising main where parts of the building are out of hose reach |
Habitable height is measured from the level of the fire engine accessway (the lowest one, if there is access at more than one level) to the finished floor of the highest habitable floor. A roof used only for M&E plant can be treated as non-habitable.
Landing valves: how many and where
Every part of each floor must be within 38 m of a landing valve: a 30 m hose plus an 8 m jet, measured along the hose route, including stair travel. That distance sets how many rising mains a floor plate needs.
| Item | Requirement (cl. 6.2.2) |
|---|---|
| Pipe size | At least 100 mm nominal bore if the main is no more than 45 m high with one landing valve per floor; at least 150 mm if it is higher, or if any floor has two landing valves |
| Valves | A landing valve with a 63.5 mm instantaneous female coupling on every floor above ground (including the 1st storey), on every basement floor, and at the roof for testing |
| Location, in order of preference | The fire lift lobby; then a smoke-free lobby or external corridor no more than 5 m from the exit staircase; then the exit staircase or a protected common area no more than 5 m from it |
| 1st storey | A landing valve is needed if any part of the 1st storey is more than 38 m from the breeching inlet |
| Protection | Pipework within a protected area agreed with SCDF; outside it, a 2-hour fire-rated enclosure. No rising main in a shaft with gas, steam or fuel pipes or electrical cables |
Clause 6.2.5 also asks for a standby fire hose next to each rising main, except in Purpose Group II buildings: 63.5 mm diameter, 30 m long, stored within 2 m of the landing valve in a marked cabinet.
Breeching inlets
The breeching inlet is where firefighters connect to charge a dry riser, or to supplement a wet one. Clause 6.2.3 requires:
- a fire engine accessway or access road within 18 m of the breeching inlet;
- the inlet visible from that accessway;
- connecting pipework between the inlet and the riser as short as possible. SCDF's notes limit the total pressure loss in a dry rising main to 6 bar at the design flow.
Wet riser supply, flow and pressure
A wet rising main has to supply water on its own, so clause 6.2.4 sets the supply and performance:
| Item | Requirement |
|---|---|
| Storage | A suction or storage tank able to supply 27 L/s for at least 30 minutes, fed from the public main by a pipe of at least 150 mm. A break tank that is not the storage tank holds at least 11.5 m³ per wet rising main. Domestic tanks cannot be used. |
| Flow, three landing valves open | 27 L/s in residential buildings; 38 L/s in non-residential and mixed buildings. With more than one main, residential mains need 27 L/s each, and non-residential mains 38 L/s for the first plus 19 L/s for each additional main, up to a total cap set by purpose group |
| Running pressure | Between 3.5 bar and 5.5 bar at each landing valve, with up to three fully open |
| Static pressure | No more than 8 bar at the hose when the nozzle is shut, so a pressure control valve and relief pipe are needed |
| Pumps | In a fire-compartmented pump room whose floor is not below the main floor level |
During construction
Rising mains are installed as the building goes up. Clause 9.9 of the Fire Code asks for all rising mains, dry and wet, to be working on every storey except the uppermost three as soon as the uppermost completed storey reaches 24 m. Plan the temporary breeching inlet and access for that stage in the construction sequence, not after topping out.
Common mistakes
- Measuring height from the wrong level. Habitable height runs from the lowest fire engine accessway, not from the ground floor or the basement.
- Checking 38 m as a straight line. Coverage is measured along the hose route, round corners and down stairs, so long floor plates often need another riser.
- Forgetting the basement. Basements need dry rising mains whatever the building height.
- Breeching inlet out of sight. An inlet more than 18 m from the accessway, or hidden behind landscaping or a gate, comes back from review.
- No pressure control on wet risers. The 8 bar static limit means tall wet risers need pressure control at the lower floors.
- Risers sharing a shaft with services. Gas, fuel or steam pipes and electrical cables are not allowed in the riser shaft.
Related guides
- Fire hose reel requirements in Singapore
- Sprinkler hazard classification under SS CP 52
- SCDF fire safety plan submission
- Sprinkler hydraulic calculations
How Newham can help
Newham's fire protection design service includes wet and dry riser design (riser sizing, landing valve placement and breeching inlet locations), sprinkler layouts and hydraulic calculations, fire pump selection and hose reel coverage, formatted for SCDF submission. Newham prepares the design and drawings. It is not a QP: where the submission needs Professional Engineer endorsement, Newham coordinates review by a Singapore-registered PE, quoted separately. Pricing a fire protection tender instead? See our BOQ and estimation services. Book a call to scope a package.