Wallpaper Calculator — How Many Rolls Do I Need?

Complete Guide to Calculating Wallpaper

Wallpapering a room is one of the most rewarding DIY projects you can tackle, but getting the quantities right is crucial. Order too few rolls and you risk batch differences when re-ordering. Order too many and you waste money on unused material. Our wallpaper calculator accounts for the key variables that determine exactly how many rolls you need.

Understanding UK Wallpaper Roll Sizes

The standard wallpaper roll in the UK measures 10.05 metres long by 0.53 metres wide (approximately 10m x 53cm). This has been the industry standard for decades and is what you will find at B&Q, Wickes and independent decorating shops. However, some alternatives exist:

Pattern Matching Types Explained

The pattern repeat is the single biggest factor affecting how many rolls you need beyond the basic room size. There are three main types of pattern matching:

Free match (random match): The wallpaper has no discernible pattern repeat. Examples include plain textures, stippled effects and some subtle designs. This is the most economical option as there is virtually no waste from pattern matching. Each strip simply butts up to the next regardless of alignment.

Straight match: The pattern lines up at the same height on adjacent strips. If the pattern repeat is 53cm, every 53cm the design repeats identically. You cut each strip at the same point, and the pattern aligns horizontally across the wall. Waste depends on how the repeat divides into your wall height — if your height is not an exact multiple of the repeat, you waste the remainder from each strip.

Offset match (half-drop): The pattern on adjacent strips is offset by half the repeat distance. For a 53cm repeat, every other strip shifts down by 26.5cm. This creates a diagonal pattern flow and is common in geometric and floral designs. Offset matching typically produces the most waste as you alternate between two different cutting positions.

Paste-the-Wall vs Paste-the-Paper

Modern wallpapers in the UK come in two main application types, and the choice significantly affects both the ease of hanging and the amount of waste:

Paste-the-wall wallpaper is manufactured with a non-woven backing that does not expand when wet. You apply adhesive directly to the wall with a roller, then position the dry paper. Key advantages include:

• No soaking time needed — the paper does not expand, so you can work faster
• Easier repositioning as the dry paper slides on the wet paste
• Less risk of tearing during application
• Can be dry-stripped when you want to remove it later — simply peel off in sheets
• Ideal for DIY beginners

Paste-the-paper is the traditional method. You apply paste to the back of each cut strip and let it soak for the manufacturer's recommended time (usually 3-5 minutes) before hanging. The paper expands slightly when wet, which must be accounted for:

• Better adhesion on challenging surfaces
• Available in a wider range of designs, especially premium and heritage papers
• Preferred by professional decorators for heavy and embossed papers
• Requires a pasting table and more workspace

Measuring for Alcoves and Chimney Breasts

Many UK homes, particularly Victorian and Edwardian properties, have chimney breasts and alcoves that complicate wallpaper measurements. Here is how to handle these:

1. Chimney breast: Measure the front face width and both side returns separately. The chimney breast front is often a popular location for a feature wall with a bold pattern.
2. Alcoves: Measure each alcove wall (back and two sides) independently. The short returns on either side of the chimney breast often need partial-width strips, which increases waste.
3. Bay windows: Measure each angled section of the bay as a separate flat surface. Allow extra wallpaper for the tricky cuts around the window frame.
4. Sloped ceilings: If wallpapering a loft conversion with sloped ceilings, measure the tallest and shortest points. Calculate based on the tallest point as each strip must cover the full height.

How to Minimise Wallpaper Waste

Even with careful calculation, some waste is unavoidable when wallpapering. However, you can minimise it with these strategies:

• Start from the focal point: Begin hanging wallpaper from the most prominent feature (usually the chimney breast or wall opposite the door) and work outwards. Any mismatch at the end will be in the least noticeable corner.
• Cut from alternate rolls: When using a half-drop pattern, cut strip 1 from roll A, strip 2 from roll B, strip 3 from roll A and so on. This uses the offcuts more efficiently.
• Save offcuts: Keep trimmed pieces for papering above doors, below windows and for future repairs. Store flat with a note of the batch number.
• Use a plumb line: Ensuring your first strip is perfectly vertical prevents cumulative errors that lead to wasted strips being pulled off and replaced.

Wallpaper Costs in the UK

Wallpaper prices in the UK vary enormously depending on the brand, material and design:

For a typical room requiring 8-10 rolls, costs range from £40 for budget paper to £800+ for designer options. Graham & Brown and Superfresco Easy offer excellent quality at mid-range prices and are widely available in UK stores. Their paste-the-wall range is particularly popular with DIYers.

Frequently Asked Questions