What is a baffled water tank?

A baffled water tank contains internal walls known as baffles, which help to control the movement of water inside the tank. When a vehicle accelerates, brakes or turns, the baffles reduce the amount of water surging from one side of the tank to another. This makes baffled water tanks particularly suitable for transporting water in vans, trailers and other moving vehicles.

Do I need a baffled water tank for transporting water?

If you are regularly transporting water in a vehicle or trailer, a baffled water tank is recommended. Water is heavy and can move considerably inside a partially filled tank. Internal baffles help reduce this movement and create a more stable load. The tank must still be correctly positioned and securely restrained, and the weight of the tank, water and other equipment must remain within the vehicle's permitted payload. To view our full range of Baffled Water Tanks, click here.

What size baffled water tank do I need for my van?

The correct size will depend on how much water you need to carry, the available space in your vehicle and, importantly, its payload capacity. As a guide, one litre of water weighs approximately 1kg. A 500 litre tank can therefore contain around 500kg of water before you include the weight of the tank, pumps, hose reels, equipment, passengers and anything else carried in the vehicle. Always check the dimensions of the available installation space and your vehicle's payload before choosing a tank.

Should I choose an upright, tower, slimline or flat baffled water tank?

This largely depends on the space available and how you intend to install the tank. Upright baffled tanks provide a good balance between capacity and footprint and are a popular choice for vans and commercial vehicles. Tower tanks are taller and generally have a smaller footprint, making them useful where floor space is limited. Slimline tanks are designed for installations where width or available space is restricted. Flat or layflat baffled tanks have a lower profile and can be useful where overall height needs to be kept to a minimum. Always check the individual tank dimensions before ordering.

How much does a full baffled water tank weigh?

Water weighs approximately 1kg per litre, so the weight increases quickly as tank capacity increases. For example: 250 litres of water = approximately 250kg 500 litres of water = approximately 500kg 750 litres of water = approximately 750kg 1000 litres of water = approximately 1000kg You will also need to allow for the weight of the tank itself and any pumps, hose reels, frames, equipment and passengers when calculating your total vehicle payload.

How should a baffled water tank be secured in a vehicle?

A baffled tank must be securely restrained before the vehicle is driven. The baffles help control the movement of the water inside the tank, but they do not secure the tank itself. The appropriate fixing method will depend on the tank, vehicle and installation. Consider the tank's position, mounting arrangement and the forces generated by a full tank during braking and cornering. If you are unsure about installation, we recommend seeking advice from a suitably experienced vehicle conversion or installation specialist.

Can additional outlets and fittings be added to a baffled water tank?

Yes. Many of our baffled water tanks can be supplied with additional outlets and fittings to suit your installation. Options vary between manufacturers and tank models, so please check the individual product page or contact us if you require a particular outlet size, position or fitting.

Can baffled water tanks be used for drinking water?

Selected baffled water tanks are manufactured from potable-grade material and are suitable for storing drinking water. Potable suitability can vary depending on the tank material, colour and manufacturer, so always check the individual product specification before ordering if the tank will be used for drinking water.

Are baffled water tanks suitable for window cleaning and car valeting?

Yes. Baffled tanks are widely used by window cleaners and mobile car valets because they allow relatively large volumes of water to be transported in a van or commercial vehicle while helping to reduce water movement during travel. The correct capacity will depend on your daily water requirements, available installation space and vehicle payload.

What is the difference between a baffled and non-baffled water tank?

The main difference is the internal construction. A baffled tank contains internal divisions designed to reduce the movement or surge of water when the tank is being transported. A standard non-baffled tank does not provide the same level of internal water control. For stationary water storage, baffling is generally unnecessary. For applications where water will regularly be transported, a purpose-designed baffled tank is usually the more appropriate choice.

Can a baffled water tank be completely filled?

Yes, providing the tank and installation are suitable and the additional weight does not cause the vehicle to exceed its permitted payload or axle limits. It is important to calculate the weight of the water before filling the tank. One litre of water weighs approximately 1kg, meaning a 1000 litre tank can carry approximately one tonne of water alone.

Where can I learn more about how baffled water tanks work?

Our Baffled Water Tank Anatomy Guide explains how internal baffles work, the different baffling methods, common tank shapes, outlets and fittings, and other important considerations when choosing a tank for transporting water.