You will not need planning permission providing:

• For domestic heating purposes and the capacity would not exceed 3500 litres
• It is not sited forward of the principal elevation of the house
• It is not sited between a side elevation of the house and the boundary
• It is sited within 20 metres of the rear elevation
• No more than three metres in height (or 2.5 metres if sited within 2 metres of the boundary)
• It is not within the curtilage of a Listed Building