Wallpaper Quantity Calculator
How to Calculate How Much Wallpaper You Need
Planning a room makeover requires precision. Ordering too little wallpaper can result in different batch numbers and slight color variations, while ordering too much is a waste of money. This guide explains the exact science behind measuring your walls and calculating rolls.
Step 1: Measure Your Walls
First, determine the total perimeter of the room. This is the sum of the lengths of all walls you plan to paper. If you have a standard rectangular room, use the formula:
Perimeter = (Length + Width) × 2
Next, measure the height from the top of the skirting board (baseboard) to the ceiling or the bottom of the coving.
Step 2: Account for Roll Dimensions
Standard wallpaper rolls (often called "Euro" or "Metric" rolls) are typically 53cm (0.53m) wide and 10.05m long. However, always check the label, as "Double Rolls" or wide-width wallpaper will have different dimensions.
Step 3: The Pattern Repeat Factor
If your wallpaper has a pattern, you will lose a portion of each roll to ensure the pattern aligns across strips. This is the "Pattern Repeat." Common repeat types include:
- Straight Match: The pattern matches straight across the width. Minimal waste.
- Offset Match: The pattern shifts vertically. This requires more wallpaper to align correctly.
- Free Match: No alignment needed (e.g., plain textures). Zero waste from repeats.
Calculation Example
| Requirement | Measurement |
|---|---|
| Room Perimeter | 18 meters |
| Wall Height | 2.4 meters |
| Roll Coverage (approx) | 5.3 square meters |
| Estimated Rolls | 9 Rolls (including 10% waste) |
Pro Tip: The Batch Number
Always buy all your rolls at the same time and ensure they have the same Batch Number or Dye Lot Number. Variations in the manufacturing process can lead to subtle color differences that are highly visible once the paper is dry on the wall.