Mezzanine, ground level, ground floor, lower ground, gallery, multi-storey, upper, loft, attic, duplex, first, second, lower ground, LG, basement.

Even a storey is spelt differently as it is in American English.

And is any level part of a building given a nomenclature both sides of the Atlantic can understand?

[F]loor numbering in London can be confusing to visitors from outside of Europe, especially since it differs from American floor numbers. Keep in mind that London buildings use the term ‘ground floor’ to describe what seems obvious – it’s on the ground hence the name is ground floor, not what people in the States would call the first floor.

In London, the first floor is one storey up. Therefore, the first floor in London is equivalent to the second floor America, and so on.

Additionally, Londoners use the phrase ‘lower ground’ to describe the basement. In this way, the lower ground level is underground.

However, lower ground floor flats are not exactly cellars – they often have windows at the front and looking towards the terrace/garden areas in the back. This is because those clever Victorians built up the roads before constructing the houses. This gave each a ‘basement’, illumination from the stairwell, and an additional door for one’s servants use.

Then, of course, we have floor 12 Immediately below floor 14 omitting number 13. But that is another storey.

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