It is perhaps no coincidence that the modern supermarket is often a giant shed that has a roof tens of metres higher that it needs to display its merchandise. Tesco, Marks and Spencer and Saisburys are all taking advantage of the space to install mezzanine floors that can double the size of their retail space – typically up to 3,000 sq m of extra space.

Increasingly the space is used to sell non-food items such as clothes, music and health and beauty products competing directly with surrounding shops. The government has agreed to investigate the problem and a planning bill is being proposed by Lady Maddock (Lib Dem) which would allow councils to control internal space. In the last year one in five local councils have reported that supermarkets in their area have adopted this ploy to increase in size.