# How do I calculate how much wallpaper I need?

How do I calculate how much wallpaper I need?  It’s something we hear on a regular basis, so The Pattern Principle have put together this great method to getting it right every time.

You will need: a tape measure, paper, pencil and a calculator.

With each step we will run though an example based on a wall measuring is 5m wide by 2.5m high, using wallpaper which has a 64cm pattern repeat and is a standard width and length, and will appear in italics.

Step 1: Calculate the number of drops needed

Measure the width of each of the walls you want to cover in your room and divide by 52cm (our standard wallpaper width, which is in line with the UK standard, please check individual wallpaper widths first which can be found in our product descriptions).  This will give you the number of drops, round this up to the next whole number;

Example : 5m (wall width) divided by 0.52m (wallpaper width) = 9.62 drops, round up to 10 drops

Step 2: Calculate the length of wallpaper needed

Measure the height of your room and multiply the height by the number of drops to get the meterage required.

Example : 10 drops x 2.5m (room height) = 25m wallpaper length

Step 3: Calculate roll length taking any pattern repeat into account

Subtracting the stated pattern repeat of the design from the actual roll length. Our wallpaper is normally 10.05m long per roll, but check your wallpaper length first, referring to our product descriptions.

Example : 10.05m (roll length) – 0.64m (pattern repeat) = 9.41m roll length

Step 4: Calculate the number of rolls needed

Divide the wallpaper length by the roll length, you should have these figures from step 2 and 3.  Round up your answer to the nearest whole number and this will give you the number of rolls required.

Example : 25m (wallpaper length) divided by 9.41m (roll length) =  2.65 rolls.  Round up to 3 complete rolls.

Step 5: Allow extra for any wastage.

This is a personal choice, but we would always recommend purchasing at least 1 additional roll and sometimes more if it is a big or challenging room.  Consider how difficult the walls are, how skilled you are at wallpapering and how much or little you rounded up in Step 3. Please bear in mind that it’s best to have extra rolls of wallpaper handy in case of mistakes/miscalculations or future damages that you cannot predict. This way you always have some extra paper in reserve from the same supplier batch.

Example : Order 4 rolls to cover wastage, accidents and damage.  Some customers also prefer to order a further additional roll from the same batch to cover any future damage, taking your total to 5 rolls.

Step 6: Choose the perfect wallpaper for you.

Why not look at our growing range of great wallpaper by visiting our wallpaper section.

NB: This is a guide only and we would always recommend consulting your interior designer or decorator in the first instance to check your requirements, please consult our returns policy regarding wallpaper returns.