Storey building (story building)

"Storey" means a floor of a building. In Nigeria the word is mostly used in the phrase "storey building", meaning any building with at least one floor above the ground floor, as opposed to a bungalow.

Counting floors. Nigeria uses the British system:

• The ground floor is not counted as a storey.
• A one-storey building has a ground floor plus one upper floor (two levels).
• A two-storey building has a ground floor plus two upper floors (three levels).

Readers used to the American system, where the ground floor is the first floor, should allow for the difference. "Ground floor flat" and "upstairs flat" are common rental descriptions.

In everyday speech. "Upstairs" is used as a noun ("he built an upstairs"), and "storey building" can mean a family duplex, a block of flats or an office building. Listings for houses usually use the more specific word: duplex.

Building one. Adding storeys needs a structural design and building approval. Stages such as DPC, lintel and decking mark progress.

Why the counting matters. Plans, approvals and listings often state the number of floors. A buyer from the US who reads "one-storey" as a single level may be surprised to find stairs. When in doubt, ask how many levels there are, including the ground floor and any roof terrace.

Approval for storeys. Planning authorities set how many floors a building may have on a given plot and in a given area. Adding a floor to an existing building needs its own approval and a structural check, because the foundation and columns must carry the extra weight. Buildings that collapse in Nigerian cities have often had floors added without either.

Ground floor or upstairs? For tenants, ground-floor flats are easier to reach and often have more outside space, while upstairs flats are usually quieter and more secure. Water pressure and power backup matter more the higher you go.

• Nigeria and the UK: ground floor not counted; one-storey means two levels.
• US: the ground floor is the first floor, so a "two-story house" has two levels.
• Kenya and Ghana: generally follow the British system.