Understanding level, floor, and story of a building

When someone tells “he is on 3rd level”, we quickly understand that someone is on the 3rd floor. But if you look at the architectural plan, you’ll see a level marksomething like +(4’-0”). There is also another term we often use, that is “Storey“.

I’ll describe all these things in this post. So that you can understand all these jargon clearly.

Story

A story is somehow a floor of a building including its roof.

In British English, it is spelled as “Storey” and in American English, it is spelled as “Story“.

When there is more than one story then it is called “Storeys” (in British English) or “Stories” (in AmericEnglishish).

When someone says “Multi-storeys” then there is more than one story available in the building. We use the term “Multi-Storeyed building” for this purpose.

Floor

A floor is somehow a Storey. But it doesn’t need to have a roof to be a floor.

Suppose, if you stand on the roof of a single-storeyed building, you are on the 1st floor (as British English).

A floor of a building is divided as Ground floor, 1st floor, 2nd floor and so on.

But in America, floors are divided as level 1, level 2, level 3, etc.

Ground floor: Ground floor is the nearest floor of the ground. In Britain, it is called ground floor and in America, it is called level 1.

The upper floors of the ground are defined as 1st floor, 2nd floor, 3rd floor and so on in Britain. In America, those are defined as level 2, level 3, level 4 and so on.

Basement floor: Basement floor is the floor which is built below the ground. If there are several floors below the ground then these are defined as basement 1, basement 2 and so on.

Level

Although a floor is defined as a level in America, there is another level we see on the architectural plan. That is marked as something like “+(4’-0”)“.

For example, if we see a level mark as +(4’-0”) on the ground floor plan of a building. What does it mean?

When an architect makes a plan of a building, he considers the road level as ±(0’-0”). That means the road in front of the plot is considered as ±(0’-0”) level.

So, when you see a level mark as +(4’-0”) on the ground floor plan of a building, you should build the ground floor 4’ above from the road level.

From this, you can calculate the level of the different floor of a building.

Then, What will be the level of the 1st floor of the building?

To calculate the level of the 1st floor of the building, you need to know the height of the ground floor of the building.

Suppose, the height of the ground floor of the building is 11’-0”.

As the level of the ground floor is +(4’-0”). So the level of 1st floor is,

= +(4’-0″) + (11’-0″)

= +(15’-0”).

If you want to know the level of the 2nd floor, you just need to add the 1st-floor height with the 1st-floor level. That’s it.

But, what should be the level of basement floor?

As basement floor is built below the ground, you need to deduct height of the basement floor from the ground floor level to know the level of the basement floor.

For example,

The basement floor height is 9’-0”.

So, the level of the basement floor should be,

= level of the ground floor – height of the basement floor

= +(4’-0”) – (9’-0”)

= -(5’-0”).

As you now know that how to calculate floor level of a building, you can calculate the level of any part of the building.

The level of the different floor is shown in the architectural plan. I just write this post to make you understand how the level is defined.