What is a Dry Riser and Why Does It Need Testing?

If you manage a multi-storey building, you've almost certainly got a dry riser. But what exactly is it, and why does the law require it to be tested every year?

What is a dry riser?

A dry riser is a system of pipes installed permanently inside a building to help firefighters get water to upper floors quickly during a fire. Unlike a wet riser (which is always full of water under pressure), a dry riser is empty until the fire service connects their pumping appliance to the inlet breeching at street level.

Once connected, water is pumped up through the pipework to outlets on each floor — usually inside cupboards or on landings — allowing firefighters to fight the fire without having to drag heavy hoses up multiple flights of stairs.

Which buildings need a dry riser?

Under BS 9990:2015, dry risers are generally required in buildings where the floor of the highest storey is between 18 metres and 60 metres above fire service access level. This covers most:

• Blocks of flats (18m+)
• Office buildings
• Hotels
• Shopping centres
• Car parks
• Mixed-use developments

Buildings over 60 metres require wet risers instead.

Why does it need annual testing?

A dry riser sits empty and unused most of the time. Over months and years, valves can seize, seals can deteriorate, cabinets can be damaged, and pipework can corrode — all without anyone noticing. In the event of a fire, a faulty dry riser could cost lives.

This is why BS 9990:2015 requires a full pressure test every 12 months, alongside a visual inspection every 6 months in some cases. The test involves pressurising the system to check for leaks, verifying all valves and outlets operate correctly, and confirming signage is in place.

What happens if it fails?

A failed test means the system has a defect that needs remedial work before it can be certified. Common failure reasons include seized or leaking valves, damaged outlet cabinets, missing signage, and pipework corrosion. We'll provide a detailed report and, in most cases, can carry out minor repairs on the same visit.

What are the legal consequences of not testing?

Failure to maintain a dry riser can result in:

• Enforcement notices from the fire authority
• Prohibition of the building
• Insurance invalidation
• Personal liability in the event of a fire-related incident

The Regulatory Reform (Fire Safety) Order 2005 places a legal duty on the responsible person to ensure fire-fighting systems are maintained in efficient working order.