When it comes to purchasing a domestic oil tank, many consumers only consider the tank size, location and material.

But before all of that, you need to establish a suitable base for its location and whether it’ll support the tank on top. This guide talks you through oil tank base regulations, the different types of bases and the importance of choosing the right one.

Why Does My Oil Tank Need A Base?

Domestic oil tanks can hold between 650 – 3,500 litres of heating oil. Add on the weight of the tank’s material (plastic, bunded or steel) and it suddenly becomes a heavy load to place directly onto the ground. Without suitable base support, the weight of your tank could damage the surface underneath, start to sink due to soil erosion, weaken the structure of your tank or pipes, and increase the risk of environmental harm if any leaks occur.

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How To Workout The Weight Of My Oil Tank When Filled?

It is simple to work out how much your tank and oil could weigh. Follow these simple steps:

  1. Work out how much the oil will weigh using your tank’s maximum capacity
    i.e 0.79kg (1-litre of Kerosene Heating Oil) x 2,500 Litres (Tank Capacity) = 1,975kg (Max capacity oil weight)
  2. Add the max capacity oil weight to the weight of your tank when empty
    i.e 310kg (Empty tank weight) + 1,975kg (Max capacity oil weight) = 2285kg (The maximum weight of your oil tank when full.

See the chart below for an estimate of how much the oil will weigh based on oil tank capacity.

Oil Tank Capacity (Litres)      Heating Oil Weight (Kilograms)
1 Litre 0.79kg
250 Litres 197.5kg
500 Litres 395kg
750 Litres 592.5kg
1,000 Litres 790kg
1,250 Litres 987.5kg
1,500 Litres 1,185kg
1,750 Litres 1,382.5kg
2,000 Litres 1,580kg
2,250 Litres 1,777.5kg
2,500 Litres 1,975kg
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Regulations For Oil Tank Base Requirements

For the safety of you, your property, the environment, and the tank itself, there are set rules and regulations when fitting your oil tank base. These include:

  • It must be laid on a compact hardcore and level surface
  • Made from a non-combustible material (concrete or stonework)
  • It extends a minimum of 300mm from each side of the tank
  • It must be 50mm thick minimum
  • It must meet oil tank location regulations (see below)

Find out more about the legal requirements of heating oil storage at Section 5: Provisions for liquid fuel storage and supply – page 63.

Siting Your Oil Tank Base

Along with the above regulations for the base itself, you need to also account for oil tank regulations. Our oil tank regulations and oil tank location blogs provide a bit more information but to summarise, your base and tank must be:


  • 8m away from non-fire-rated buildings, eaves, structures or boundaries
  • 1.8m away from the flue terminals of oil-fired appliances
  • 600mm away from foliage
  • 1.8m away from openings in fire-rated buildings
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The Different Types Of Oil Tank Bases

There’s a variety of oil tank bases for you to choose from. Which one is best for your site is dependent on your oil tank location, the type of soil underneath and the style of oil tank you have. If you’re installing a new oil tank or replacing an existing one, our engineers will assess the area to ensure your oil tank base meets regulations, recommending one of the following bases:

  • Concrete – at least 100mm thick
  • Pre-cast Concrete – at least 100mm thick
  • Paving Slabs – at least 50mm thick
  • Stonework – at least 50mm thick
  • Pre-cast Concrete Slabs – at least 50mm thick

Installing A Heating Oil Tank Base

As part of our installation service at Oil Tanks Plus, our APHC-accredited engineers will review your existing oil tank base and recommend the right base for your new oil tank, ensuring that you comply with building regulations.

This is usually completed over the phone once we have received images of your oil tank, however, our engineers can arrange a site visit to inspect your tank and base and advise the best tank and base for your requirements.

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Finding The Best Base For You

For more information on oil tank bases, contact our friendly team who can advise you on the right base and organise a site visit.