Defining What Oil Storage Bunded Tanks Are

Hazardous liquids like domestic heating oil and others of its kind can be practically stored using bunded tanks. This type of liquid storage tank is quite distinct from many other types of oil storage tanks, much like the single skin tanks.  

Bunded storage tanks are different because they have this special feature, a secondary containment tank, referred to as the “outside skin” or bunding. This signifies that if any amount of oil will leak or ooze out from the main storage tank, you still have your peace of mind knowing that it would still be safely contained inside of the exterior wall. Hence, preventing spillage and contamination of the immediate surrounding ground is unlikely to happen.

This protective layer of the tank makes it even more robust, making this oil storage tank a much safer and more secure option. On the downside, that also makes this type of storage tank command a higher price compared to a “single skin” tank, even if both can just hold just the same exact amount of fuel.  

When Do You Need a Bunded Tank?

A bunded storage tank for fuel is being utilized by most industrial and commercial entities. They usually require an oil tank with a storage capacity of 200 liters or more.  They are also legally required in most domestic installations.

Liquid storage tanks that have the 3,500-liter capacity or more need to be bunded due to possible pollution risk they carry with them. Like for instance, bunding is essential to a tank that is to be sited in a region comes with a spillage risk and is in close proximity to public water sources such as river, stream, or lakes.  

Additional Safety Features of a Bunded Liquid Storage Tank

The “second skin’ feature for this type of storage tank not only prevents the oil or any liquid that it holds from leaking or spilling, but they also come with a number of other safety features. These vary with respect to its model, make and size of the tank.

  • These are the standard safety features of a bunded tank:
  • Equipped with a tank gauge, for assessing the amount of stored liquid the tank is holding.
  • A lockable fill point to help in deterring fuel thefts.
  • Comes with a secure fuel inspection hatch to allow for convenient access to the fuel and for cleaning purposes, too.
  • An alert system mechanism signals for sudden fuel level drops (either due to leakage or oil theft).
  • An overfill protection device keeps you from keeping too much oil in the tank.

Amount of Fuel the Bunding Can Hold

In an unlikely event that an oil leak occurs, the outer tank is actually designed to hold liquid more than the inner tank’s capacity. The fuel amount that this additional layer can hold will depend upon the model and the make of the tank, although the minimum is 110% of the inner tank fuel capacity.  

The double-layered bunded tank will also help keep the occurrence of fuel theft at bay, simply because the extra wall layer will make it very difficult to go through the tank’s inner section. And finally, the outer bund wall protects the inner tank from acquiring any damage from an impact.  




Hazardous liquids like domestic heating oil and others of its kind can be practically stored using bunded tanks. This type of liquid storage tank is quite distinct from many other types of oil storage tanks, much like the single skin tanks.  

Bunded storage tanks are different because they have this special feature, a secondary containment tank, referred to as the “outside skin” or bunding. This signifies that if any amount of oil will leak or ooze out from the main storage tank, you still have your peace of mind knowing that it would still be safely contained inside of the exterior wall. Hence, preventing spillage and contamination of the immediate surrounding ground is unlikely to happen.

This protective layer of the tank makes it even more robust, making this oil storage tank a much safer and more secure option. On the downside, that also makes this type of storage tank command a higher price compared to a “single skin” tank, even if both can just hold just the same exact amount of fuel.  

When Do You Need a Bunded Tank?

A bunded storage tank for fuel is being utilized by most industrial and commercial entities. They usually require an oil tank with a storage capacity of 200 liters or more.  They are also legally required in most domestic installations.

Liquid storage tanks that have the 3,500-liter capacity or more need to be bunded due to possible pollution risk they carry with them. Like for instance, bunding is essential to a tank that is to be sited in a region comes with a spillage risk and is in close proximity to public water sources such as river, stream, or lakes.  

Additional Safety Features of a Bunded Liquid Storage Tank

The “second skin’ feature for this type of storage tank not only prevents the oil or any liquid that it holds from leaking or spilling, but they also come with a number of other safety features. These vary with respect to its model, make and size of the tank.

  • These are the standard safety features of a bunded tank:
  • Equipped with a tank gauge, for assessing the amount of stored liquid the tank is holding.
  • A lockable fill point to help in deterring fuel thefts.
  • Comes with a secure fuel inspection hatch to allow for convenient access to the fuel and for cleaning purposes, too.
  • An alert system mechanism signals for sudden fuel level drops (either due to leakage or oil theft).
  • An overfill protection device keeps you from keeping too much oil in the tank.

Amount of Fuel the Bunding Can Hold

In an unlikely event that an oil leak occurs, the outer tank is actually designed to hold liquid more than the inner tank’s capacity. The fuel amount that this additional layer can hold will depend upon the model and the make of the tank, although the minimum is 110% of the inner tank fuel capacity.  

The double-layered bunded tank will also help keep the occurrence of fuel theft at bay, simply because the extra wall layer will make it very difficult to go through the tank’s inner section. And finally, the outer bund wall protects the inner tank from acquiring any damage from an impact.