How to Calculate Square Metres of a Room for Tiling

Posted by As'ad Mansoor on 18th May 2024

Planning to tile a room can be a fun and rewarding DIY project, but before you start, you need to know how much tile to buy. This means calculating the square metres of the room accurately. Don't worry, it's not as tricky as it sounds! Follow these simple steps, and you'll be ready to head to the store with confidence.

Step 1: Gather Your Tools

First things first, you'll need a few basic tools:

- A tape measure (or a laser distance measurer if you want to get fancy)

- A notepad and pen (or your phone’s note app)

- A calculator (your phone can do this too)

Step 2: Measure the Room

Rooms come in different shapes and sizes, but let’s start with the basics—rectangular or square rooms.

Measuring a Rectangular or Square Room

1. Measure the Length and Width:

- Grab your tape measure and measure the length of the room. Write this number down.

- Next, measure the width of the room and note it too.

2. Calculate the Area:

- Now, multiply the length by the width. This gives you the area in square metres.

- For example, if your room is 5 metres long and 4 metres wide:

Area = Length X Width= 5m x 4m = 20m Square

Measuring an Irregularly Shaped Room

If your room isn't a perfect rectangle, don’t worry! Just break it down into smaller rectangular sections.

1. Divide the Room:

- Sketch a rough diagram of your room and divide it into smaller rectangular sections. Label each section (A, B, C, etc.).

2. Measure Each Section:

- Measure the length and width of each section separately and write these measurements down.

3. Calculate the Area of Each Section:

- Use the same formula (Length × Width) for each section.

- Add up the areas of all sections to get the total area.

- For example, if Section A is 3m × 2m, and Section B is 4m × 3m:

Area A = 3m x 2m = 6m Square

Area B = 4m x 3m = 12m Square

Total Area = 6m + 12m = 18m Square

Step 3: Account for Obstacles

Got any built-in cabinets, bathtubs, or other obstacles that won’t need tiling? Measure these too!

1. Measure the Obstacle:

- Measure the length and width of each obstacle.

- Calculate the area (Length × Width).

2. Subtract the Obstacle Area:

- Subtract this area from the total area of the room.

- For instance, if the obstacle is 1m × 0.5m:

Obstacle Area = 1m x 0.5m = 0.5m Square

Adjusted Total Area = 18m Square - 0.5m Square = 17.5m Square

Step 4: Add Extra for Waste

Always add a bit extra to your total to account for waste from cutting and future repairs—10% is a good rule of thumb.

1. Calculate Extra Tiles:

- Multiply the total area by 10% (0.10).

- Add this to the total area.

- For example:

Extra Tiles = 17.5m Squared x 0.10 = 1.75m Squared

Total Area with Extra = 17.5m Square + 1.75m Square = 19.25m Square

Step 5: Final Calculation

Finally, round up the total to ensure you have enough tiles. Tiles are usually sold in boxes that cover a specific area, so round up to the nearest whole number of boxes.

By following these steps, you’ll know exactly how much tiles to buy, ensuring you have enough for your project and minimising waste. Happy tiling!