Posted by Wall Panels World on 3rd May 2024

Wall Square Metre Calculator | Calculate Wall Area Instantly | UK

Wall Area Calculator

For calculating the square metre of walls

How To Calculate Wall Area

Here's a simple guide to calculate the area of a wall, minus the area of any windows, doors, or other obstructions:

What you'll need:

  • Tape measure
  • Pen and paper (or calculator)


  1. Measure the Wall Dimensions:
    • Use your tape measure to find the wall's height (from floor to ceiling) in metres (m).
    • Then, measure the wall's width (distance across the wall) in metres (m).
  2. Calculate the Total Wall Area:
    • Multiply the height (m) by the width (m). This gives you the wall's area in square metres (m²).
    • Formula: Area (m²) = Height (m) x Width (m)
  3. Measure Obstructions (Windows & Doors):
    • For each window or door on the wall, measure its height (m) and width (m).
  4. Calculate Obstruction Area (Each):
    • Multiply the height (m) of each obstruction by its width (m). This gives you the individual area of each window or door in square metres (m²).
  5. Subtract Obstruction Area (Total):
    • Add up the individual areas of all obstructions you measured in step 4.
    • Subtract this total obstruction area (m²) from the total wall area (m²) you calculated in step 2.
    • Formula: Usable Wall Area (m²) = Total Wall Area (m²) - Total Obstruction Area (m²)


  • Wall height: 2.4 metres (m)
  • Wall width: 3.2 metres (m)
  • Window height: 1.2 metres (m)
  • Window width: 1.5 metres (m)
  1. Total Wall Area: 2.4m x 3.2m = 7.68 m²
  2. Window Area: 1.2m x 1.5m = 1.8 m²
  3. Usable Wall Area: 7.68m² - 1.8m² = 5.88 m²


  • If you have multiple windows and doors, repeat steps 4 and 5 for each obstruction and add their individual areas together before subtracting from the total wall area.

This method allows you to determine the actual usable area of the wall after accounting for any windows, doors, or other obstructions.

Measuring For Wall Panelling

The previous guide explained calculating a wall's usable area, which is crucial for installing  wall mouldings and panelling. Here's how to adapt that method with some additional considerations:

Wall Area Calculation (Same as before):

  • Follow the steps 1-6 from the previous guide to calculate the usable wall area (m²) after accounting for windows, doors, and other obstructions.

Additional Considerations for Mouldings & Panelling:

  • Moulding Thickness: Measure the thickness of your chosen moulding in millimetres (mm). This is important for accurate material calculations later.
  • Panel Size: If using pre-made panels or wall panelling kits, note their size (height and width) in millimetres (mm).
  • Panel Layout: Decide on your panel layout. Will they run vertically, horizontally, or in a grid pattern? This can affect material usage.
  • Wastage: Allow for a 10% buffer for material wastage due to cutting errors or unexpected trims.

Calculating Material Quantities:

  • Moulding: Once you have the usable wall perimeter (length + width in metres), convert it to millimetres for moulding calculations. Then, divide the total perimeter (mm) by the moulding thickness (mm) to find the total moulding length required in metres (m).
  • Panels: Divide the usable wall area (m²) by the individual panel area (m²) to determine the number of panels needed. Add 10% for wastage and round up to the nearest whole number.


  • Usable wall area: 5.88 m²
  • Moulding thickness: 15 mm (converted to 0.015 m)
  • Panel size: 1 m x 0.5 m (0.5 m²)
  • Moulding: Let's say the wall perimeter is 10 metres (converted to 10,000 mm). Total Moulding Length = Perimeter (mm) / Moulding Thickness (mm) = 10,000 mm / 0.015 m = 666.67 metres. As you can't buy part of a metre of moulding, round up to 667 metres.
  • Panels: We need 5.88 m² / 0.5 m² = 11.76 panels. Adding a 10% buffer and rounding up gives us 13 panels.

How To Calculate Square Footage

  1. Measure the length and width of the area in feet.
  2. Multiply the length by the width. This gives you the area in square feet (sq ft).

Formula: Area (sq ft) = Length (ft) x Width (ft)

So, if your wall is 10 feet long and 8 feet wide, the area would be 80 square feet (sq ft).

Conversion from metres to square feet (if needed):

If you have measurements in metres, you can convert them to square feet using a conversion factor of 10.7639. Here's a simple formula:

  • Area (sq ft) = Area (m²) x 10.7639

How To Calculate Square Metre

This guide will help you calculate the area of a flat surface in square metres (m²), the standard unit of area used in the UK.


  1. Measure the Length and Width:
    • Use your tape measure to find the length and width of the area you want to calculate in metres (m).
    • It's important to take accurate measurements for a precise result.
  2. Multiply Length by Width:
    • Once you have both measurements in metres, multiply the length by the width.
    • This gives you the area of the space in square metres (m²).
    • Formula: Area (m²) = Length (m) x Width (m)


Let's imagine you're finding the area of a rectangular carpet that's 2.5 metres long and 1.8 metres wide.

  1. Length (m) = 2.5
  2. Width (m) = 1.8
  3. Area (m²) = 2.5m x 1.8m = 4.5 m²

Therefore, the carpet's area is 4.5 square metres.

Top Tips:

  • If your measurements are in centimetres, convert them to metres before multiplying.
    • Remember, there are 100 centimetres (cm) in 1 metre (m).
    • For instance, a measurement of 175 centimetres is equal to 1.75 metres (175 cm / 100 cm/m).
  • Double-check both your measurements and calculations for accuracy.
  • This method works for any flat surface with a rectangular shape.

Understanding Square Metres:

Think of a square metre as the area covered by a square with sides that are each 1 metre long. By multiplying the length and width of any flat surface (in metres), you're essentially calculating how many of these 1 metre x 1 metre squares would fit within that space.