How to Calculate Floor area For Tiles

When purchasing tiles for your floor estimating the number of tiles required can be a daunting task especially if your floor area is not a square or a rectangle.

This is heightened by the fact that most tiles come in dimensions

of 2” x 2”, 4” x 4”, 6” x 6 “, 9” x 9”, 12”x 12” and 18” x 18” square inches though there are other variations depending on the manufacturer and consumer taste.

Similarly, it is no doubt that not all your rooms will conform to perfect squares or rectangles and you therefore have to be sure how you will find out how many tiles you need for the job. 

Before we delve deep into the whole concept of measuring floor area and tiles, let us take a look at some of the measuring units that are necessary for floor area measurement and how they relate to each other.

1m = 100 cm = 3.2808 feet = 39.370 inches

1 square meter = 10000 square cm = 10.7639 square feet =1,550 square inches

Do not worry about the decimal points, we will show you how to approximate your floor area tile without cracking your calculator. Furthermore, it is important to note that you need to buy a few extra tiles for cutting allowances.

What you Need

Before you begin this exercise you will need; a pen (or pencil), a measuring tape, and a calculator. You may also need someone to hold the tape for you on the other end.

Step 1; Calculate the Area of the Room

This is the most important step of any tiling exercise. You need to be certain of what area you want to place tiles, and then calculate the area of that space. If your room has wardrobes and other places that may not need tiles you can reduce that are by calculating the area of the smaller region and subtracting from the total are you calculated initially.

How to find area of a square and a rectangle 

Measure the two sides of the floor in centimeters or meters, the longest side is called length (denoted by L), and the shorter side is called width (denoted by W). For a square both length and width are equal.

Multiply the two sizes. I.e.

L X W = area of the room

How to find the area of a circle

If you have a circular room you want to tile then here is how to find the area of the room. 

Measure the diameter of the room in centimeters; the diameter is the length of any straight line that passes through the centre of the room and touches the ends of the room.

The area of a circle if given by the formula 3.14 x r x r; where R is half of the diameter. If you find this irritating you can divide the house into rectangles and calculate the area of each rectangle and add the resulting areas to get one area of the room.

How to measure the area of a triangle

To find the area of a triangle, use the formula;

(Base x height) divided by 2. The base is one length of the triangle while the height is the length of the triangles head from a 90 degree point on the base length.

For other floor area shapes, divide the floor area into several squares or triangles and calculate the respective areas of the rectangles. Then add all the resulting areas into one figure and you would have approximated the area of the floor area.

Once you have the size of the room, write it down neatly since you will be using it again in consecutive steps.

Step 2; calculate the area of each tile

Measure the length and width of the type tile you want to buy for you floor. Usually, tiles come in standard square lengths as mentioned above.

So here is a quick calculation of each of the tiles.

1"x1" = 1” squared

2"x2" = 4” squared

3"x3" = 9” squared

4"x4" = 16”squared

6"x 6" = 36” squared

8"x 8" = 64” squared 

2"x4" = 8” squared

2"x8" = 16” squared

4"x 8" = 32” squared

60 x 60 cm = 3600 cm square (granite tile)

Using the inches to meters converter described above, you can convert the area of your floor into square inches so that you have a solid measuring to work with.

For example if your room measure 15 m by 10 meters; then the area of your room is 150sqm or 1615 square feet or 232500 square inches.

Step 3; Estimate the number of Tiles you need for each Room

The next step will be to identify how many tiles will fit into the room perfectly. However, at this point it is important to note that while every measure is taken to ensure you get a perfect measure of the number of tiles needed for a room, they are just approximations and you need to add between 5-15 % more tiles to cater for breakages and shortage. 

This means that the number of tiles required will be equals to; area of the room + waste.

Since you have the area of the room and the size of the tiles, divide the area of the room with the area of the size of the tile and you will get the number of tiles needed.

Let us look at an example of a room with length 20 and width 10m

Area of 200sqm = 2152 square feet = 310000 square inches

200sqm will use 1”x 1” tiles as = approx. 310,000 tiles + waste

200sqm will use 2” x 2” tiles as = approx 77,500 tiles +waste

200sqm will use 3” x 3” tiles as = approx. 34445 tiles + waste

200sqm will use 4” x 4” tiles as = approx. 19375 tiles + waste

200sqm will use 6” x 6” tiles as = approx 8611 tiles + waste

200sqm will use 8” x 8” tiles as = approx 4844 tiles + waste

200sqm will use 2”x 4” tiles as = approx. 38750 tiles + waste

200sqm will use 2” x 8” tiles as = approx. 19375 tiles + waste

200sqm will use 4” x 8” tiles as= approx. 9699 tiles + waste

200sqm will use 60cm x 60 cm tiles as = approx. 556 tiles + waste

Bottom Line

While it may not be easy to understand how to calculate floor area for tiles by yourself, you can always contact a professional to do it for you. Similarly, using a professional minimizes the number of wastage tiles during installation.

Be sure to add about 5%-15% extra tiles beyond the approximated tiles so that you do not run out of them during the process. Finally ensure you use enough grout to hold the tiles firmly on the floor.