Overview
Work out square metres for floors, walls, rooms and other rectangular surfaces.
Objective
Use the correct measurements, units and method to produce an accurate, clearly labelled result.
What You Need
- Length and width measurements
- Measurements in metres
- Calculator if needed
Before You Start
Write down the value or dimensions you have, including their units. Decide exactly what unit or result you need before calculating. Keeping the units visible makes errors much easier to spot.
How to Do It
- Measure the length.
- Measure the width.
- Convert both measurements to metres if necessary.
- Multiply length × width.
- Write the answer in square metres (m²).
Worked Example
A floor is 4.5 m long and 3.2 m wide. 4.5 × 3.2 = 14.4 m².
Useful Tips
- Convert centimetres or millimetres to metres before multiplying.
- Break irregular spaces into rectangles and add their areas.
- Allow for waste separately when ordering materials.
Common Mistakes
- Adding length and width instead of multiplying.
- Using mixed units.
- Writing m instead of m².
Important Notes
Conversion factors and measurement standards can vary by country or context. When accuracy matters, confirm the standard being used and keep enough decimal places until the final answer.
FAQ
When should I round the answer?
Keep the full value during the calculation and round at the end to a level of precision suitable for the task.
Why should I always write the units?
The unit tells you what the number represents and helps reveal mistakes when converting or calculating.