Heating Oil Tanks: A Definitive Guide

Heating Oil Tanks


Just moved into a property that has Heating Oil Tanks? Don’t panic!

Our Definitive guide to Heating Oil Tanks will help you understand all about the different types, prices and sizes, plus how to maintain your oil tank and protect yourself against oil theft.


What type of Heating Oil tank do I need?

There are four main general types of Heating Oil tank designs:


Single skin tanks(plastic/metal)

A single skin plastic tank will be the cheapest design, with the metal version being slightly dearer. This design is tightly regulated by the industry as it offers the least protection. The positioning of these tanks on your property will have guidelines – please see below for more information.

Bunded tanks(plastic/metal)

Bunded tanks are effectively a tank within a tank. Once again the plastic version will be cheaper than a metal one. This design is to ensure that if the inner tank splits or is overfilled, the outer tank will contain the spillage and protecting the enviroment. The outer skin also protects the inner tank from damage through possible collision and weathering ( heavy rain entering the oil tank/strong sun light weakening plastic seams). Some bunded tanks are designed so you can position it underground, allowing you to access the tank to re-fill when needed.

Open Bund tanks

The tank can be either single skin or bunded but is also protected by a secondary bund that is normally made from a concrete block or brick wall that surrounds the tank. This will bring an additional cost to the initial purchase price of the tank. This design is usually used in  commercial sites as it can take up a lot of room and is visually unattractive.

Bunded tanks with integral fire protection

Exactly the same design as the bunded tanks, but the inner tank is protected by a high quality fire retardant material. This design is at the higher end in terms of budget. The advantage of this design is it allows you to position the tank practically anywhere on your property. You can choose from 30 to 60 minutes fire resistance.

Plastic or Metal

the two have their pro’s and con’s.



  • cheaper on cost
  • light and easy to manoeuvre into position
  • more variety of sizes, capacity and shapes.


  • Lack of security
  • prone to split and crack along the top of the tank due to bad weathering



  • more secure than plastic
  • theft deterrent
  • Durable material longer life


  • More expensive
  • heavier and harder to manoeuvre
  • less variety on sizes, capacity and shapes


Installing my Oil Tank

Competent Person 

When it comes to installing Heating Oil Tanks, you must use a certified OFTEC engineer. An OFTEC registered engineer will be up to date on all the existent regulations and will be able to advise on all aspects of location.



It is unlikely that a fire could be started by a domestic fuel storage tank and its contents. However, tanks are required to comply with fire separation distances in order to adequately protect the stored fuel from a fire or heat source that may originate nearby.
Tanks should be sited:
1.8m away from non-fire rated eaves of a building
1.8m away from a non-fire rated building or structure (e.g. garden sheds)
1.8m away from openings (such as doors or windows) in a fire rated building or structure (e.g. brick built house/garage)
1.8m away from oil fired appliance flue terminals
760mm away from a non-fire rated boundary such as a wooden boundary fence
600mm away from screening (e.g. trellis and foliage) that does not form part of the boundary

Don’t forget that when you order your heating oil, the delivery company will need access to your tank. Most Heating oil deliveries are made with a HGV road tanker.  Can the vehicle get close enough to the tank to make the delivery? Will their hose reach? Can they access your drive way?

Positioning your tank close to the boiler is also a good idea. In the event of running the tank dry, the boiler will cut out and could possibly create an air lock. Having the tank located close to the boiler will minimise the distance the oil travels to the boiler to re-ignite.


Supporting your tank

The need to provide a suitable base and support for your fuel tank is of paramount importance for reasons of both safety and environmental protection. The base should be:

  • Adequate for the weight of the tank
  • Non-combustible and level
  • Constructed of concrete, paving stones or stonework
  • Large enough to extend 300mm beyond all sides of the tank.

If a fuel storage tank is not adequately supported the tank itself can be weakened, leading to the eventual failure and escape of the stored fuel. During the life of an installation a fuel storage tank base will need to provide continual structural support, even though ground conditions may alter from season to season and year to year.


Where do I purchase the right tank for me?

Ultimately, online is the best place – there are plenty of sites to choose from that offer a range of oil tanks that can help you compare prices and designs that suit your needs.

Tank Prices

Prices generally range from around £500 for a small single-skinned tank to more than £2,500 for a large integrally bunded fire retardant  one. Price will also depend on size, which can vary from around 1,000 to more than 3,500 litres.

Size of tank for my property

How much Heating Oil will I need?

This is a very difficult question as it is different to every individual.

  • How big is your house?
  • How warm do you like your home to be?
  • How efficient is your boiler?

These are some questions you should ask yourself when purchasing your oil tank.

Keeping an eye on how many deliveries you’ve had, as well as the literage over the course of 12 months will help you get into a routine when it comes to ordering and budgeting.

Our experience in this industry tells us that an average household(3/4 bedroom semi) uses approximately 4000 litres a year.

Buying Heating oil is always cheaper when you buy in bulk – the more you order in one delivery, the cheaper the price. This can be a contributing factor when deciding on the size of your oil tank. Buying a smaller tank may be cheaper in the short run, but being able to buy in bulk enables you to play with the oil market. Oil prices fluctuate everyday and having the room to fill your tank when the price is low is a great advantage.

Tank Gauges

All tanks will be equipped with either a sight gauge or an electronic device called a watchmen. These devices help you read the level of the tank and warn you when your tank is low on Heating Oil.


Maintenance is important to ensure your oil tank retains its integrity. As owner of the tank, you have a responsibility to ensure its safe keeping. It is best practice to have your oil tank inspected during your annual heating service. You should also check your pipe work periodically to ensure its integrity and that it is not leaking.

At Lucas Fuels we inspect every tank we deliver to, informing the customer of any defects that we may find. Replacing faulty gauges, tank lids and screw caps is a service we do for free for all our customers to ensure the quality of your oil and the safety of your oil tank.