Fire fighting
water storage

Automatic fire sprinkler systems are installed for two main reasons; property protection or life safety. In both cases their efficiency in controlling and extinguishing fires has protected lives and the environment for over one hundred and twenty years.

Cylindrical steel tanks

Cylindrical sectional tanks are manufactured in aluminium, galvanised and stainless steel. The range of materials on offer provides customers with cost effective and project specific options in the fire protection, potable and irrigation water storage sectors

Product overview

GRP sectional tanks

Balmoral GRP sectional water tanks provide water storage in capacities of 1m3-1300m3 and are erected to heights of 4m in 1m and 0.5m increments. With an unrivalled reputation for quality and service, Balmoral GRP sectional tanks can be pre-insulated and carries full industry approval

Product overview

Steel sectional tanks

Hot pressed steel tanks are designed and manufactured by Balmoral Tanks under the brand name of Horseley Bridge. Established in 1880, Horseley Bridge pioneered the use of bolted sectional water tanks

Product overview

Epoxy coated steel tanks

Epoxy coated steel tanks form an integral part of the company’s industry offering. These products are widely specified by the water, wastewater, desalination, food processing, agricultural, chemical, biogas, anaerobic, fire and digester sectors

Product overview

Tank installation

Balmoral Tanks provides full installation services for all products. On major projects a detailed pre-start site survey is included as standard and this can be made available for all projects on request

Product overview

Technical services

Comprehensive inspection, maintenance, repair and refurbishment services

Product overview

Fire protection technical guide

Automatic fire sprinkler, wet riser and mist system tanks are installed for two main reasons; property protection or life safety.

In both cases their efficiency in controlling and extinguishing fires has for over one hundred and twenty years protected lives and the environment and it should be accepted that all sprinkler systems will protect lives by restricting fire spread and protection escape routes.

Property protection systems are often installed at the request of the building occupier’s insurer to protect the business by ensuring the building and contents are protected against fire.

Some systems are installed to comply with building or fire regulations primarily to protect employees, the public and fire fighters from the risks of fire. This type of system should be more accurately referred to as ‘enhanced availability’ sprinkler systems but are more commonly called ‘life safety’ sprinkler systems and include a range of added features which reduce the possibility that the system will ever be non-operational due to scheduled service and maintenance being carried out.

In both of these cases an essential part of the system is the water supply. This can take the form of a direct supply from the local water service main with or without a booster pump or, more reliably, having water stored in a tank with a pump or pumps to deliver the water to the sprinkler system.

The most common arrangement is a single water storage tank with two fire pumps, each capable of meeting the needs of the sprinkler system.

For enhanced reliability, the water storage tank can be split into two half-capacity tanks. This ensures that there is always a water supply available to the sprinkler system, even when one tank (or any of its equipment) is being serviced or maintained.

Balmoral Tanks gratefully acknowledges BAFSA for its kind assistance with the text used on this page

BAFSA logo

1Standard of construction for fire fighting tanks

It is essential that the water storage tank is of robust construction and is designed and constructed to need little maintenance or servicing. Balmoral fire fighting water storage tanks are designed in accordance with best practice and technical information relating to corrosion protection and design considerations. They are installed such that the need for emptying for maintenance is reduced to a period of not less than 10 years.

Where sprinkler systems are designed to the LPC Rules for Automatic Sprinkler Installations incorporating BS EN 12845:2009 the most commonly used water storage tanks have LPCB approval. LPCB listed tanks must comply with the rigorous manufacturing and test standard LPS 1276.

Type ‘A’ tanks with a 15-year maintenance free period can still be provided for contracts designed to the now obsolete BS 5306 Part 2:1990.

A list of LPCB-approved tanks can be found in the LPCB ‘Red Book’ and on their website. These tanks come in sizes from 5m3-1300m3 depending on the hazard category of the sprinkler system. If a larger capacity is required a combination of approved tanks can be used.

The relevant sections of the LPC Rules for Automatic Sprinkler Installations incorporating BS EN 12845:2009 that apply to water storage tanks for sprinklers are:

TB 203 - Care and maintenance of automatic sprinkler systems

TB 204 - Sprinkler system grading

TB 209 - ESFR sprinkler protection

TB 218 - Water supply diagrams

TB 221 - Sprinkler in schools

TB 224 - Water storage tanks (cisterns)

TB 229 - Variations to BS EN 12845 rules

TB 233 - Water supplies for life safety systems

Sprinkler tanks are also listed by the US insurers’ certification body UL for use on specified sites. For contracts designed to NFPA 13 (US National Fire Protection Association Codes) either an FM Approvals or LPCB listed tank can be used subject to insurers’ approval.

3Positive head or suction lift
4Corrosion protection of steel tanks
6Water quality
7How much water is needed?
8Full holding or reduced capacity
9What duration of water should be provided?
10Tank support base
11Tank painting

The external surface of the tank can be painted to choice by the client but the tank manufacturer should be consulted to ensure that any coating used does not damage the tank wall and does not invalidate the LPCB listing and any manufacturers’ warranty.

12Tank location
13Planning approval
14FM Approvals
15Tank shell
16Tank roof
18Corrosion protection
19Tank heating and insulation

Balmoral FireFlow™ vortex inhibitor

Fire fighting water tanks require a large, fast flowing volume of water with a vortex inhibitor playing a key role in preventing air being drawn into the system and reducing the flow. Vortex inhibitors are fitted to the outlet pipe of the pumped water system.

Standards require the usable water level to be no less than 100mm above the lowest suction point, the height of the vortex inhibitor also affects the effective capacity within a sprinkler tank.

Simple vortex inhibitors are available commercially; however the Balmoral FireFlow vortex inhibitor provides a significantly improved design which optimises both the capacity of the tank and the flow rate.

Balmoral’s vortex inhibitor was designed using computation fluid dynamics to remove turbulent areas that would otherwise reduce the flow rate.

Balmoral’s unique design fully meets the requirements of BS EN 12845 standards, including pipe dimensions, flow rate and mechanical strength, but with the advantage of increasing the effective capacity of the tank and decreasing the suction loss through the vortex inhibitor by an industry-leading 30%.

The injection moulded vortex inhibitors are made from structural thermosetting polyurethane, are fully corrosion resistant and range from 80-450mm in diameter. These PU materials are used by Balmoral’s offshore division at water depths of 2000m and beyond.

Balmoral FireFlow vortex inhibitor fluid dynamics

fluid dynamics analysis of the Balmoral FireFlow vortex inhibitor which clearly shows a smooth and uniform flow leading to drag reduction and a decrease in suction requirements

Accessories and ancillaries

Fire fighting sprinkler tanks

For optimum functionality the following accessories will usually be installed on a Balmoral fire fighting sprinkler tank:

A reliable water supply connection (usually direct from the service main) capable of refilling a full holding capacity tank in 36 hours or with sufficient flow to replenish a reduced capacity tank in 30, 60 or 90 minutes as necessary
Flow testing facility to prove the flow rate of the infill. Adequate drainage should be provided for disposal of water during testing
Float or Ball valve/s on the tank infill pipe. These must be located in a secure housing on the tank roof
A duel element electric immersion heater to prevent ice forming on the water surface in the area of the ball/float valves on external tanks
Electric float switches to transmit signals to the BMS or fire control panels to indicate the high/low level volume of water in the tank
A drain valve at low level
A gated ladder to allow personnel to get to the inspection and maintenance platform on the tank roof
Third party pump suction pipe with an electrically monitored gate valve, locked open
A rigid roof that excludes daylight, can withstand snow loads and prevents any matter falling into and contaminating the water
Most tanks have a vortex inhibitor fitted at the inlet of the pump suction pipe to prevent air getting drawn into the pump. For NFPA and FM Global contracts the vortex inhibitor must be constructed as detailed in their data sheets
Trace heating and lagging to all exposed water filled pipes, by others
A 25mm warning pipe is installed just above the high water level to give an early warning of ball valve malfunction
An AB airgap arrangement with side spill over weir assembly and cowl
A larger bore overflow pipe
An access hatch is provided at ground level to allow access during tank construction and evacuate personnel in an emergency
A contents gauge or device which shows the level of water in the tank
Some sprinkler tanks will have a fire brigade inlet installed. This allows the brigade to ‘top up’ the sprinkler water storage if necessary
A sump can be formed in the concrete tank base. This allows the sprinkler pump to draw water to a lower level from the tank.

Pipework configuration

The inlet or delivery pipe can enter the tank through either the side wall at the top of the tank or into a raised chamber. Flow can be controlled through a ball valve, equilibrium float valve or automatic float switch.

Overflows should be positioned in accordance with the required air gap, and all outlets (suction), drains and overflows will come through the side walls of the tanks.

Overflows and warning pipes terminate at high level, horizontally, and can be extended to the floor if required.

Pipe connections

Customers are asked to provide full details when ordering. The type of pipe connection should be specified together with the relevant standard to which the coupling flanges are drilled or the pipes screwed. To assist delivery, the size and position of each connection should also be specified at the time of ordering. Ball and gate valves and all pipework, including bends and flanges, can be supplied if specified at the time of ordering.

Connections can be supplied as flanged stools to BS4504, ASA or DIN standards, or, for small pipework, screwed sockets to BS1387. The connections are fitted to the plates in positions agreed at the time of order.

Low level access panels

The low level access panel was introduced by Balmoral Tanks to address confined space issues. Essentially, when a tank is being constructed onsite, it will ultimately become a confined space as the installation team completes the build.

Ball Float Valve

These are installed at the end of the incoming water supply pipe and automatically keep the tank full.

Product literature and certification

Product literature

Product certification

Case studies

Hangar and office building at Sharjah Airport
Hangar and office building at Sharjah Airport
Application Fire fighting sprinkler tank
Tank type Pre-mill galvanised steel cylindrical

10.2 x Ø11.7m

Capacity Two tanks with total capacity of 2050m3
Scope of work Design, manufacture, install, test
Installer Balmoral Tanks
Sir C Duncan Rice Library, University of Aberdeen
Sir C Duncan Rice Library, University of Aberdeen
Application Potable, non-potable water storage and fire fighting sprinkler tank
Tank type GRP sectional tanks

15 x 3 x 3.5m | 5 x 3 x 3m | 2 x 2 x 2m | 2 x 2 x 2m
and one-piece 1370 litre break tank

Scope of work
Design, manufacture
Main contractor
Pihl UK
Installer SPARKS



Additional information (if known)

Please give an indication of required tank capacity
Is your tank installation to be located indoors or outdoors?
Please provide foundation type/information, if known
Please provide accessibility distances around the proposed tank location

View Balmoral Tanks terms and conditions of use.

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