If you want to estimate how many rolls of wallpaper you will need when renovating a room, you will find it helpful to use **KALK.PRO's advanced wallpaper calculator**.

This application will determine the number of wallpapers for the entire room or for certain walls individually by area, which can be useful in non-standard rooms with 5 or more walls or in cases where you plan to use different types of textures.

Estimator takes into account the repeat pattern (rapport), side overlap, doors, windows, which allows you to calculate the surface area of the application more correctly and optimize the consumption of rolls. It will also calculate the total price of the purchase based on the roll price.

## How many wallpaper rolls do I need?

There are two popular ways to calculate wallpaper — **by wall area and by wall height**.

The first method is to calculate the area of a roll of wallpaper as **one solid roll** of wallpaper, which means that when you wallpaper the roll may end in the middle of the wall and a seam may appear in a visible spot. This is the **wrong way** to calculate and this is what most applications think.

The second way is that if the length of the roll will be less than the height of the wall (from floor to ceiling), then take a new roll, and the remains of the previous are used for smaller areas, such as under a window or over a door.

KALK.PRO wallpaper calculator uses the second method because it is **more correct and shows real results**, although it slightly increases the estimate compared to other applications.

## How to use wallpaper calculator? Manual

If you want our tool to estimate the number of wallpaper rolls correctly, you must select the method of calculation (by room area or wall area), then find all the necessary values and enter them in the fields of the application.

For the first method:

ceiling height, m;

room width and length, m;

For the second method:

ceiling height, m;

wall length, m;

number of walls, pcs.

You can also activate the «Windows» and «Doors» fields. They allow you to make a more accurate calculation. Also, if you have other places that are not expected to have wallpaper (e.g. furniture, bathtub, stairs) it is acceptable to use the «Windows», «Doors» fields for these purposes as well.

The tool calculates the wallpaper equally correctly in situations where the roll partially (2) or fully (3) overlaps the opening.

After that, you need to fill in the parameters of the wallpaper:

- roll width, cm;
roll length, m;

repeat pattern (rapport), cm;

alignment reserve, cm;

side overlap, cm;

shift the pattern (optional);

cost, $.

**Alignment (trim) reserve**— an additional value for each strip in case of horizontal unevenness of ceilings/floors. The optimal value is 5-15 cm.

**Side overlap**— partial overlap of one roll with another (for «overlapping» method).

**Shift the pattern**— displacement by half of the pattern (leads to increased consumption of wallpaper).

**Repeat pattern (rapport)**— is the repeating part of the pattern in height and/or width. The value is indicated on the roll and measured in centimeters. If you have a wallpaper without a pattern, enter «0» in the field.

### How many rolls of wallpaper do I need for a room? Table

In some cases, when you need to know how many rolls of wallpaper for a room, to get an approximate result is more convenient to use reference tables.

#### Roll width 53 cm and length 10 m

Ceiling height < 2,5 m | Ceiling height 2,6-3 m | ||

Room area, m | Number of rolls, pcs | Room area, m | Number of rolls, pcs |

6 | 5 | 6 | 7 |

10 | 6 | 10 | 9 |

12 | 7 | 12 | 10 |

14 | 8 | 14 | 10 |

16 | 8 | 16 | 11 |

18 | 9 | 18 | 12 |

20 | 9 | 20 | 13 |

22 | 10 | 22 | 14 |

24 | 10 | 24 | 15 |

26 | 11 | 26 | 16 |

28 | 11 | 28 | 17 |

30 | 12 | 30 | 18 |

#### Roll width 70 cm and length 10 m

Ceiling height < 2,5 m | Ceiling height 2,6-3 m | ||

Room area, m | Number of rolls, pcs | Room area, m | Number of rolls, pcs |

6 | 4 | 6 | 5 |

10 | 4 | 10 | 6 |

12 | 5 | 12 | 7 |

14 | 6 | 14 | 7 |

16 | 6 | 16 | 8 |

18 | 6 | 18 | 8 |

20 | 6 | 20 | 9 |

22 | 7 | 22 | 10 |

24 | 7 | 24 | 10 |

26 | 8 | 26 | 11 |

28 | 8 | 28 | 12 |

30 | 8 | 30 | 12 |

#### Roll width 106 cm and length 10 m

Ceiling height 2,5 m | Ceiling height 2,6-3 m | ||

Room area, m | Number of rolls, pcs | Room area, m | Number of rolls, pcs |

6 | 3 | 6 | 4 |

10 | 3 | 10 | 5 |

12 | 4 | 12 | 5 |

14 | 4 | 14 | 5 |

16 | 4 | 16 | 6 |

18 | 5 | 18 | 6 |

20 | 5 | 20 | 7 |

22 | 5 | 22 | 7 |

24 | 5 | 24 | 8 |

26 | 6 | 26 | 8 |

28 | 6 | 28 | 9 |

30 | 6 | 30 | 9 |