Oil tank regulations

Which rules apply

A fixed heating oil tank of up to 3,500 litres serving a home in England falls under requirement J7 and the guidance in Section 5 of Approved Document J. Replacing a tank counts as new work, not a repair, so the rules apply in full even when the new tank goes in the same spot. Bigger tanks, and tanks at businesses, fall under the stricter oil storage regulations instead.

Welsh Ministers publish separate Building Regulations guidance; Scotland uses the domestic Technical Handbook (standard 3.23); Northern Ireland has its own Building Regulations. The distances and the bund triggers are close to England's in practice, and installers in each nation know the local wording.

Distances

When a bund is required

GOV.UK lists the situations where a domestic tank must have secondary containment holding at least 110% of its contents:

• spilled oil could run into an open drain or a loose manhole cover;
• the vent pipe cannot be seen from the fill point during delivery;
• the tank is within 10 metres of inland or coastal waters;
• it is within 50 metres of a drinking water source such as a well, borehole or spring;
• oil could run over hard ground into water or a drinking water source;
• the tank is in the inner zone of a groundwater source protection zone 1;
• it holds more than 2,500 litres.

The installer's risk assessment decides the rest. Most now fit bunded tanks as standard.

Base, pipework and labelling

The base must be non-combustible, flat and level, and larger than the tank. Concrete at least 100 millimetres thick or paving slabs at least 50 millimetres thick are usual, extending 300 millimetres beyond the tank all round. The supply pipe needs protection where it runs above ground and a fire valve that shuts off oil automatically if there is a fire at the boiler. A durable label on the tank must explain what to do if oil escapes.

Who signs it off

Use an installer registered with a competent person scheme, such as OFTEC, and they self-certify the work and notify the council. Otherwise you must make a building notice application and pay for the inspection. GOV.UK warns that without approval you may not have the certificates you need when selling, and that both the installer and the owner can be held responsible for non-compliant work.

Farms

Fuel stored for farm vehicles and machinery is "agricultural fuel oil". Where a farm keeps more than 1,500 litres in total it must be bunded to 110% of the tank (or 25% of the total in a multi-tank bund, if more), kept 10 metres from inland or coastal water, built to last 20 years, and notified to the Environment Agency at least 14 days before a new store is built. Heating oil kept separately for the farmhouse follows the household rules instead.

If oil escapes

Report any spill that could reach water to the Environment Agency on 0800 80 70 60, day or night. More on our leaking oil tank page.