We have produced a "How To" video which explains the factors that affect wallcoverings and also has a masterclass on how to hang wallcoverings.

Click here to watch the video.

We also have a Product Support Manual which provides information on everything from how to calculate the number of rolls needed for a room to how it is printed and how to interpret wallpaper symbols.

A couple of sections from this manual are reproduced below:


Understanding pattern repeat and pattern match
It would appear that the understanding of pattern match and pattern repeat is one of the more difficult areas of wallpapering. Understanding the pattern repeat is particularly relevant when calculating how much wallpaper is required, as buying too much can be expensive, whereas not buying enough could mean going back to the shop and finding that the supplier no longer has any of the same batch left in stock.
Probably the biggest misconception is the belief that pattern repeat and pattern match are one and the same thing, it simply being a different word. This is not the case and it needs to be clearly appreciated that pattern repeat can be very different from pattern match.

Pattern repeat
The pattern repeat is identified by a written figure (eg. 26cm, 52cm etc) and is the distance measured before the same part of the design repeats itself along the length of wallpaper. 
This distance can vary and is dependent upon how many times the design is engraved onto the circumference of the print cylinder or screen. 
As an example and for description purposes only, we will assume that the circumference of a print cylinder is 60cm. If the same part of the design was engraved into the cylinder four times, it would mean that the circumference of the cylinder (60cm) is divisible by 4, hence the design repeat would be every 15cm. 
If the design repeats itself 3 times, it would be 60cm divided by 3, a pattern repeat of 20cm. 
Or of course, it may, in effect, repeat itself only once - therefore being 60cm repeat.
This distance is useful for calculating how much extra should be allowed on each drop of paper on hanging. The amount of waste to be added to a length to be hung can never be greater than the pattern repeat indicated.

Pattern match
The pattern match will generally be shown as either a written direction: e.g. half drop, random, etc. or a symbol (LEFT) or a combination of both (RIGHT) 
Its purpose is to identify where, in relation to the other side of the wallpaper (across the width), the matching part of the design is. To help with this you will find that in most cases wallpapers are trimmed through the design for ease of matching on hanging.
If the matching half of the design falls on the same horizontal plane as the other side, then it is a straight match. If, on the other hand, the matching part of the design falls somewhere between two match points, in relation to the other side of the sheet, then it is an offset match.
In a lot of cases (and this is where the confusion may come in) manufacturers may use the words ‘Pattern match’ on the label, but actually show the repeat against it, or vice versa.

Calculating number of wallpaper drops needed
For purposes of calculation it is wise to ignore windows and doors and treat walls with them in as full walls. It is likely that as much paper will be used cutting and piecing around the recesses as would be used on a straight drop.
1  Start by measuring each individual wall, from corner to corner, to determine its length. 
2 Divide the width of the roll into the width of the wall, this will determine how many lengths are required for that wall. Continue this for all the walls and total up all the drops together to calculate the total amount of drops needed for that room.
Remember that full widths of wallpaper should not be turned into a corner as walls are never even and creasing may occur. Only 
2-3cm should be turned into the next wall. For purposes of calculation, any part widths should be calculated as full widths.
Calculating length of drops
1 To calculate the length of full drops required, measure the height to be decorated and add to this 30cm (15cm top and bottom) for trimming. Then add on the pattern repeat as identified in the pattern book or on the label, e.g. 52cm. 
2 Once the total required length has been calculated, divide it into the length of the roll (normally 10 metres). This will identify how many drops can be achieved from a full roll. 
Remember to only count full drops
NOTE: If selecting a wallpaper that has a ‘random’ or ‘free match’, or is recommended to be ‘reverse hung alternate lengths’, there is no need to add on the pattern repeat when calculating the drop length.
Calculating number of rolls needed
1 Simply divide the total number of drops needed for the room, by the amount of drops achievable from a roll. This figure is the total amount of rolls needed.
For designs with a pattern match of up to 26cm add 10% up to the nearest full roll, for wastage. For designs with a pattern repeat of over 26cm add 15-20%.
This guide assumes that domestic LENGTH and width wallpaper is being used, normally 10 metres by 52cm. It also assumes that there is no match on the wallpaper, i.e. it is either a free or random match or is reverse hang alternate lengths. 
Understanding cleanability information
Understanding the definition of the wallpaper symbols, as printed on the front of labels, can be perplexing and may cause confusion to consumers and decorators alike. This is particularly so with the ‘cleanability’ symbols, i.e. washable, scrubbable, etc. where their interpretation differs from that of the manufacturers.
From a consumer’s viewpoint it would seem reasonable that if a wallpaper label says ‘washable’, then it means that the product can be washed. This belief may make up part of the selection process and may be used to determine whether the paper is appropriate for the intended room. 
Manufacturers on the other hand are obliged to follow the guidelines and to use only the wording and symbols as set in the BS EN233 ‘Wallcoverings in roll form’. This is the European standardisation document that 
is intended to ensure continuity and consistency throughout the industry.
Whilst the paper has to perform as the symbols suggest, it needs appreciating that wallcoverings, in the main, are only made of paper. As such there are some types of stain that could not realistically be expected to be removable, as some stains are not removable from carpets or fabric.
When manufacturers evaluate wallpaper to determine a standard they have to do so absolutely objectively. There can be no deviation from as instructed, nor can a subjective opinion be expressed. It is this ‘interpretation’ that divides manufacturers and consumers.
The test itself is done using a calibrated ‘rubbing’ machine that utilises a weighted head with differing materials fixed underneath to simulate what may be used in the home. It uses ‘sponge’ to simulate sponging, ‘felt’ to simulate soft cloth and ‘bristles’ to simulate scrubbing. The standard is achieved if the paper sample demonstrates no visible damage having been rubbed a controlled number of times.
If wallpaper is tested to a selected level, i.e. scrubbable, and it fails, then the wallpaper will be re-tested to the standard immediately below, in this case ‘washable’.
Only under ‘spongeable’ is the expectation made very clear as to what may be achievable. The other descriptions are unfortunately vague and in no other case is it specifically identified what may or may not be removable in a home situation. 

Download pdf cleanability symbol guide