Oil tanks with a capacity of 3,500 litres or less should be fitted at least 1.8 metres from non-fire rated walls or from flu outlets.
If a clearance space of 1.8 metres is not possible, protection measures stated in British Standard BS 5410: Part 1: 1997 must be provided by introducing a 30 minute fire-resistant wall. The fire wall must extend at least 300mm above the end points of the oil tank. When installing an oil tank, any exposed eaves which form part of a roof within 1.8 metres of the top of an oil storage tank must have a 30 minute fire resistant wall installed. Cladding can also be applied to prevent a fire from spreading to the roof.