What is a Dry Riser?

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A dry riser, also known as a dry standpipe, is a crucial component of a tall building’s firefighting infrastructure. It consists of an empty vertical pipe running through a building, usually in a stairwell or dedicated fire fighting shaft, with outlet valves on each floor. The pipe is not permanently connected to a water supply. Instead, when needed, firefighters can quickly connect their hoses to an inlet at ground level, allowing them to pump water up the pipe and access it on any floor to fight a fire.

This painting delves into the critical yet often overlooked world of dry risers in firefighting. Through a cross-section of a building, it visualizes the essential system of vertical pipes and the heroic efforts of firefighters connecting hoses to combat flames. The artwork encapsulates the readiness and challenges of maintaining these lifesaving systems, contrasting the drama of fire against the calm efficiency of firefighting efforts.

Fresh Kit’s Quick Guide to Dry Risers

Dry risers are a legal requirement in the UK for most buildings over 18 metres tall (and under 60m), which is approximately the reach of fire engine hoses. Their primary purpose is to save precious time for firefighters, who would otherwise need to drag heavy hoses up multiple flights of stairs to reach a fire on upper levels. With a dry riser, they can immediately begin tackling the blaze on any affected floor.

How Do Dry Risers Work?

From the outside, a dry riser is a relatively simple system. The vertical pipe, usually made of galvanized steel, runs from an external inlet box at ground level up through the building to the highest floor. The inlet, covered by a breakable seal, allows firefighters to connect their pump’s hose rapidly.

On each floor, or at least every ten floors for very tall buildings, there are landing valves where firefighters can connect their hoses to access the pumped water supply. These valves are in cabinets recessed into the wall, with doors labelled “Dry Riser Outlet” for easy identification.

Once connected and charged with water at ground level, the dry riser becomes a temporary water main for the building. Firefighters can connect to it on any floor and have an immediate high-pressure supply to combat the fire without running hoses from their engines.

Dry Riser vs Wet Riser

The critical difference between a dry and wet riser is that a wet riser is permanently filled with water. It has a dedicated water tank and pumps at the top of the building, maintaining constant pressure on the pipes.

Wet risers offer an even faster response, as firefighters can immediately connect their hoses on any floor without needing to charge the system first. However, they are more complex and expensive to install and maintain, requiring dedicated water storage, pumps, and pressure regulation.

In the UK, wet risers are generally only used in tall buildings over 50 metres, where the added speed is necessary. Dry risers are sufficient for most high-rise buildings.

Maintenance and Testing

While a dry riser may seem like an inert system, regular maintenance and testing are essential to ensure flawless operation in an emergency.

All dry risers in the UK must be visually inspected every six months by a competent person, checking for any damage, corrosion or leaks in the pipework and valves. Inlet and outlet covers must be in place and undamaged.

A pressure test must also be conducted every year. This involves a professional specialist verifying that your system can deliver a pressure of at least 12 bar for 15 minutes. Any faults must be immediately rectified.

Records of these inspections and tests must be kept on-site for inspection by the fire authority. Failure to maintain a dry riser system can lead to enforcement action.

Overcoming Challenges

While dry risers are a straightforward concept, their installation and use can face various challenges, particularly in older or complex buildings.

One issue is the routing of the pipework. In a new building, this can be planned from the design stage to ensure a clear, protected shaft up through the structure. However, retrofitting a dry riser into an existing building may require creative routing through existing spaces, which can be disruptive and costly.

Another challenge is ensuring adequate water pressure and flow at the top of very tall buildings. While fire engine pumps are powerful, pumping against gravity over great heights pushes them to their limits. In some cases, particularly above 20 floors, additional booster pumps may be needed partway up the dry riser to maintain pressure.

Access can also be an issue, especially in densely built urban areas. Fire engines need to be able to park close enough to the inlet to connect their hoses, which may require maintaining dedicated access routes and parking areas.

Despite these challenges, dry risers remain an essential tool for firefighters. The ability to quickly establish a water supply on any floor of a burning building can be the difference between a small, contained fire and a devastating blaze.

The Future of Dry Risers

As buildings become taller and more complex, dry riser technology must evolve to keep pace. One approach could be to have wet risers on the lower floors of tall buildings combined with dry risers on the upper floors. This hybrid approach balances the speed of a wet riser with the simplicity and lower maintenance of a dry riser.

Another development worth considering is using intelligent monitoring systems for dry risers. These can use sensors to continually check for leaks, corrosion or pressure drops, alerting maintenance staff immediately if a problem is detected. This could help ensure the riser is always ready for action.

There is a case for research into alternative water sources for dry risers, particularly in areas with limited mains water supply. Ideas include using seawater for coastal buildings or recycled greywater from the building. While these pose challenges regarding corrosion and filtration, they could help make dry risers viable in a broader range of locations.


Dry risers are an unsung hero in the world of firefighting. This simple pipe system, hiding in plain sight in thousands of buildings, is critical in allowing firefighters to quickly tackle blazes on any floor.

While they may seem passive most of the time, regular maintenance and testing are vital to ensure they are ready to perform their lifesaving function immediately. As buildings evolve, so will dry riser technology, ensuring firefighters always have the tools to keep us safe.

So, the next time you’re in a high-rise building, take a moment to appreciate the dry riser. It may look like a pipe on the wall, but it could one day be the difference between life and death.

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