Coating from tiles it was and remains best choice when it comes to bathroom decoration. After all, such properties of ceramics as strength, moisture resistance, and aesthetics are ideally suited to the operating conditions of a given room. But due to the fact that the cost of tiles is not the lowest, there is always the intention of finding out how to calculate the tiles for the bathroom. Nobody needs extra expenses for repairs, but there must be exactly enough material so that during the repair process you are not distracted by unnecessary troubles.

What is this article about?

Room measurements

To calculate the tiles for the bathroom, you need to take a ruler and measure the room. That is, measure the length of all sides of the walls. It is easier to measure an area represented by a rectangle or square. In the first situation, two sides are measured, in the other, one.

If there are various curved areas in the room, all parts are measured. The results are recorded and a scale plan is drawn up. He will help in drawing up a design project for the renovation. On the plan you can indicate the installation locations of plumbing fixtures and furniture.

Basic calculation formulas

When calculating bathroom tiles, you should use the basic formulas for calculating the perimeter of a rectangle and its area.

The area is determined according to the formula:

and the perimeter is calculated as follows:

where the letters express the parameters:

• S – area expressed in square meters;
• P – room perimeter;
• D – wall length;
• L – width;
• H – wall height.

The area of ​​all walls is calculated as the total sum of the found areas of all walls. Having found this value, the areas of those surfaces that are not subject to cladding (door and window openings, the space behind the bathroom) are minus from it.

Please note: sometimes, for reasons of economy, they do not plan to tile the wall, which will be hidden behind the bathroom. When choosing this finishing option, the wall area is calculated by measuring the height from the side of the bathroom.

These formulas are the basis for calculating the number of tiles for the bathroom. In addition, to determine the quantity facing material information such as:

• laying diagram;
• planned color scheme of finishing;
• the need for adjustment to the pattern of elements;
• presence/absence decorative elements(borders, inserts) in addition to the main coating.

Example of volume by area calculations

To illustrate how to calculate the number of tiles in a bathroom, let's look at examples. Presumably, the volume of material must be calculated for a room with the correct rectangular dimensions, in which the following measurements were made and recorded:

• shortened wall - 2.3 m;
• long wall - 3.2 m;
• wall height - 2.5 m.

The calculations will look like this:

The perimeter of the room with these measurements will be 11 meters = 2.3*2 + 3.2*2.

The area of ​​the shortened wall is 5.75 m2 = 2.3 * 2.5.

Whereas the area of ​​a long wall will be 8 m2 = 3.2*2.5.

The total area of ​​the room will be 27.5 m2 = 5.75*2+8*2.

But the cladding area will be smaller. Since the area of ​​the doorway will be removed from it. Which is 1.32 m2 = 0.6 * 2.2, where the width of the opening is 0.6 meters and its height is 2.2 m.

Then the area that needs to be tiled will be equal to 26.18 m2 = 27.5 - 1.32.

In this case, the floor area for cladding will be 7.36 m2.

Examples of calculations for floors

For example, choice flooring fell on square-shaped elements with side lengths of 50 by 50 cm. Therefore, the area of ​​each tile will be equal to 0.25 m2.

To determine how many tiles you need for a bathroom floor, you should divide the floor area by the area of ​​one element. If we take the data from the example above, then 7.36/0.25 = 30 tiles (rounded up).

Previously, we looked at how to calculate bathroom tiles of the same type. However, not many people use the same type of tile. The option of combining elements is often used. In this situation, it remains to be seen how many tiles would have to be purchased different types. Specialized computer programs can come to the rescue with this.

Count flooring perhaps in a different way. That is, count not according to the floor area, but individually. To do this, you also need to know the length and width of the bathroom. If we use the data from the previous example, the sides of the room will be 230 cm, 320 cm. If the tiles have a side of 50 cm, then the width will require 230/50 = 4.6 elements (rounded to 5 whole pieces). This means that 5 tiles will fit in one row in width. Next, we calculate how many rows will be laid in length 320/50 = 6.4, round to 7. Then multiply 5 pieces in one row by 7, we get 35 pieces. Don't forget to add a couple or three pieces in reserve. Therefore, we will inform the seller that we have purchased 38 pieces.

Now let’s compare the results obtained from the example, where calculations were carried out by floor area and the data where the quantity was calculated individually. The difference is 8 pieces. That is, so many would not be enough to cover the floor and would have to be purchased in the future. The second calculation option is more accurate and it makes more sense to use a piece-by-piece calculation.

Wall covering quantity

To calculate the amount of tiles for the bathroom on the walls, it is best to perform calculations separately for each partition. 250 cm (wall height) must be divided by 33 (tile side in cm) = 7.57 (or exactly 8) pieces - in a row according to the height. 230 cm (wall width) divided by 33 (tile side in cm) = 6.97 (or 7) pieces will lie in a row according to the width. We multiply 8 with 7, we get 56 units with sides of 33 and 33 cm. Needed for a smaller wall. By analogy, the number of tile samples needed to finish the larger side is calculated. Makes 80 tiles.

Accounting for door space

For example, the height of the door is 180 cm. Divide it by 33, we get 5.45. Round down, it comes out to 5 pieces in height. The door width is 75 cm, divide it by 33 cm (side of the element), we get 2.27. Rounding down, we get 2 elements in width. We multiply 5 by 2, we get 10 pieces. If we subtract them, for example, from 80, we get 70 elements.

Counting the tiles on the wall, where part of it is covered by the bathroom, is done in a similar way.

Example of calculations with decorative inserts

For calculations, consider materials with the following dimensions:

• wall elements rectangular shape- dimensions 20 cm x 30;
• pencils - 1.5 x 20 cm;
• borders - 10 cm x 20 cm.

We count the total number of borders with pencils. Why divide the perimeter by the length of each fragment. We remove the width of the doorway from the perimeter value. With our data it will be like this: (11 - 0.75)/0.2 = 51.25. Round up to a higher value, we get 52.

Since the pencils are placed on each side of the border tile, its consumption will double, in other words, 104 pieces will be needed. Next, the area that the tile will occupy is calculated.

Please note: if a direct layout of elements is chosen, then 5% of the material should be added to the calculated number of tiles, and when choosing more complex layout patterns (for example, with a diagonal arrangement of elements), the calculated number of elements is increased by adding 15% of the material.

These examples are enough to do the calculations yourself. Knowing them, calculate the required number of tiles, taking into account doorways and inserts of decorative elements.

This question is one of the main ones: how many tiles are needed for work, that is, how to calculate the number of tiles for the floor. Here we need calculations to accurately determine required quantity tiles for a bathroom or other room.

To do this, measure the length of the room and divide by the length of one ceramic tiles. Also measure the width of the room and divide by the width of the tiles. Then multiply the two results obtained, after which you will get the required number of tiles for a given room.

1 option for calculating the number of tiles

For example, room length 3 meters and width 2 meters. Ceramic tile size 200x150 mm. It is advisable to convert to one unit of measurement:

1. Room length 3 meters = 300 cm, and the width 2 meters = 200 cm.
2. Tile 200 mm = 20 cm, and the width 150 mm = 15 cm.
3. Now all that remains is to calculate:
4. Divide the length of the room by the length of the tiles = 300/20=15 ;
5. Divide the width of the room by the width of the tiles = 200/15= 13,3 ;
6. Let's multiply the two obtained indicators = 15*13,3= 200 .

Happened 200 tiles for this room.

Option 2 for calculating the number of tiles

There is another calculation option that may be easier for you than the previous one. First you need to calculate the area of ​​the room and the area of ​​one tile. And then divide the floor area by the area of ​​the tiles.
Let's look at it with an example. Let's take the indicators from option 1. Room length 3 meters and width 2 meters. Ceramic tile size 200x150 mm.
Here we convert the tile size to meters:
200 mm = 0.2 meters
150 mm = 0.15 meters
Floor area in the room: 3 m * 2 m = 6 m 2
Area of ​​one tile: 0.2 m * 0.15 m = 0.03 m2
The floor area is then divided by the area of ​​one tile: 6 m 2 / 0.03 m 2 = 200 pcs. That is, we will need 200 tiles.

Getting started finishing works in the bathroom, you first need to calculate and purchase required amount material. It is advisable to buy the entire volume at once, since the next batch may differ in tone, so calculations must be made very accurately. In this case, tiles are used to finish the walls and floor. Manufacturers offer material various shapes and size. The number of tiles needed for the bathroom will largely depend on which collection is preferred. There are several calculation methods that we will introduce you to today.

Preparatory stage

Before you begin the calculation, you need to carefully measure the bathroom using a tape measure or rangefinder. The following parameters are required for the calculation:

• Wall height.
• Width of walls.

If the walls have correct form, it will be enough to make two or three measurements. If there are niches or various protruding elements, you will need to measure their parameters too and clarify the dimensions of the door.

Even if at first glance the walls seem perfectly smooth: square or rectangular, be sure to take several control measurements. This will avoid errors in calculations.

Required quantity of floor tiles

First way

Calculations begin with determining the floor area. To do this, its length is multiplied by its width. Then the area of ​​one tile is calculated in the same way. After this, the first value is divided by the second, and the resulting result is rounded up. The result is an approximate value, which experts recommend increasing by 5%, multiplying by correction factor 1.05. The resulting value is again rounded to the nearest whole number.

As an example, consider a bathroom that has a ceiling of 2.65 m, walls of 1.8 m and 1.7 m and a door 0.6 m wide. In such a case, if floor tiles 33 cm by 33 cm, you will need: ((1.8*1.7)/(0.33*0.33))=28.1 pieces; 29*1.05"31 tiles.

Second way

We begin calculating the number of tiles for the bathroom by determining the number of tiles that will need to be laid in length and width. To do this, divide the length and width of the room by the length and width of the tiles, respectively. We multiply the resulting values ​​by each other, round to the nearest whole number and also increase by 5%.

Based on the above example, we obtain the following sequence of calculations:

1. 1.8/0.33=5.5 pcs.;
2. 1.7/0.33=5.2 pcs.;
3. 5.5*5.2=28.6 pcs.;
4. round the value obtained in step 3 to 29;
5. 29*1.05=30.45 pcs., i.e. To finish the floor (after rounding up) you need to purchase 31 tiles.

If, when calculating using one of the methods, it turns out higher value, it's worth choosing. However, it is worth noting that sales consultants prefer to use the first option.

Required quantity of wall tiles

First way

To determine how many bathroom tiles are needed for wall cladding, we calculate the perimeter of the room. To do this, we sum up the lengths of all its walls. If we're talking about For a standard bathroom, just add the length and width and multiply by 2. In our example: (1.8+1.7)*2=7 m.

Based on the perimeter, the required number of friezes is calculated. To do this, the width of the door is subtracted from the perimeter of the bathroom. The resulting value is divided by the length of the frieze or border, respectively.

If you wish, you can save money by not covering the part of the wall located under the bathtub. In this case, it will be necessary to subtract the area pertaining to this area from the general calculations.

So, for example, assuming that the dark tiles will be laid to a height of 1 m, we find that the height of the light top will be equal to: 2.7 m -1 m – 0.08 m (frieze height) = 1.62 m. Now you can calculate the required number of tiles. For this:

• We calculate the area that light and dark tiles will occupy.
• We divide the resulting values ​​by the area of ​​one tile.
• Round to the nearest integer value.
• We increase by 5%.
• Round to the nearest whole value.

In our example we will need:

• Dark tiles: (7-0.6)*1/(0.2*0.4)=52.5 pcsÞ53 pcs * 1.05=55.56Þ56 pcs;
• Light tiles: (7-0.6)*1.62/(0.2*0.4)=55.05 pcsÞ56 pcs * 1.05=90.3Þ91 pcs.

If planned decorative inserts, then the amount of light or dark tiles must be reduced by the amount of purchased decor

Second way

In this case, we lay out the layout of each wall to understand how many tiles can be placed in horizontal and vertical rows. In this case, the tiles that need to be cut are taken into account as whole. We increase the resulting value by 5% to insure ourselves in case of marriage or battle. We calculate the required amount of dark, light tiles and curbs and go shopping.

Thus, knowing the above methods, everyone can independently calculate how many tiles are needed for a bathroom. You just need to take the correct measurements, decide on the type of tile, as well as how it will be placed on the wall and floor.

9778 0

In order not to stop work when renovating a bathroom due to a lack of material or not to think about where to put the excess, it is important to correctly calculate the need for tiles. There are several calculation methods, depending on the type of tile laying and differing in accuracy.

When decorating a bathroom in a monotonous manner, when all surfaces are covered with the same type of tile laying (straight, diagonal or offset), the need for tiles is calculated in square meters or by the piece.

The amount of ceramics required to perform complex artistic cladding must be calculated separately for each independent fragment of the room’s decoration. Let's consider these methods.

Calculation of ceramic consumption in square meters

When choosing a monotonous type of tile laying, measurements are taken of the dimensions: length, width, height - the room in meters accurate to a hundredth of a centimeter, rounding up fractions of a centimeter.

Calculating the cost of finishing the floor

To calculate the quadrature of the floor, the metric values ​​of the length and width of the floor are multiplied, after which the resulting result is rounded to whole units. If laying is performed in a direct way or “offset”, 10% must be added to the resulting amount. If ceramics are laid diagonally, 15% is added to the floor area.

For example:

The square footage of a room with a length of 4.21 meters and a width of 2.34 meters is:

• 4.21 x 2.34 = 9.8514 sq. m. Rounded up to 10 square meters. meters.

Add 10%:

• 10 x 1.1 = 11 sq. m.

With the diagonal method, you need to add 15%, it turns out: 10 x 1.15 = 11.5 sq. m. ≈ 12 sq. m.

Calculation of material for wall cladding

The surface area of ​​the bathroom walls is calculated by multiplying the perimeter of the room and its height, the resulting value is also rounded up to whole units:

(4.21 + 2.34 + 4.21 + 2.34) x 2.68 = 35.108 sq. m. ≈ 36 sq. meters.

Then measure the height and width doorway in meters accurate to the centimeter, rounding fractions of a centimeter down. By multiplying these values, we get the area of ​​the doorway, rounding it down to tenths of a square meter.

For example:

• the area of ​​a doorway measuring 2.1 x 0.8 is 1.68 square meters. ≈ 1.6 m2;
• the area of ​​the doorway is subtracted from the surface area of ​​the walls: 36-1.6 m = 34.4 sq. m.

To the result obtained, add 10 or 15% depending on the type of tile installation and round up to whole values:

• direct or offset method: 34.4 sq. m. x 1, 1 = 37, 84 sq. m. ≈ 38 sq. m.
• diagonal method: 34.4 sq. m. x 1.15 = 39.56 sq. m. ≈ 40 sq. m.

If you do not cover the walls behind bathroom, then the area of ​​this hidden surface is also subtracted from the area of ​​the walls, but this saving leads to a weakening of the waterproofing of this area behind the bathroom, which is fraught with damage to the finish in the adjacent room due to seeping condensate.

Having calculated how many square meters of tiles are needed for repairs, they purchase finishing material. The packaging of the ceramics indicates how many square meters of cladding it contains. To calculate the required number of packs correctly, the need for tiles in square meters must be divided by the square footage indicated on the packaging and rounded up to whole values.

Calculation of tile consumption per piece

Piece counting has a smaller error, but this also has the advantage back side— with this method, there is no material left in case of accidental damage to the tiles during installation or unexpected spot repairs to the cladding.

With this method, measurements of the dimensions of the room are also taken, but in centimeters, rounding fractions of a centimeter up to whole values. For example, a length of 420.5 cm is rounded to 421 cm, a width of 233.7 cm is rounded to 234 cm, and a height of 267.6 cm is rounded to 268 cm.

Then the retail chain looks for a certain tile and measures the dimensions of one tile. For example, the tile chosen for the walls is 15 cm wide and 20 cm long, and for the floor they chose ceramics 20 x 20 cm. To calculate how many pieces of tiles are needed for wall cladding, the consumption must be calculated for each wall separately.

Piece calculation of ceramics for walls

In our example, the bathroom has two walls with dimensions of 421 x 268 cm and 234 x 268 cm. If the tiles are laid vertically, then from floor to ceiling it will fit 268:20 = 13.4 pieces. With a minimum width of tile joints, this value must be rounded to 14 products.

The length on one wall will fit 421:15 = 28.06 pcs., on the second - 234:15 = 15.6 pcs. Let's round up to 28 and 16 products.

We calculate how many pieces will be needed for finishing:

• 14 x 28 = 392 pcs.; multiply by two walls, we get 784 products.
• 14 x 16 = 224 pcs.; We also multiply by two walls, we get 448 products.

For vertical surfaces, 1232 pieces will be required, but from this amount you need to subtract the number of tile pieces corresponding to the area of ​​the doorway. Suppose doorway has dimensions of 210 x 80 cm. Its height will fit 210:20 = 10.5 pcs. Round down to 10 pieces. The opening width will fit 80:15 = 5.33 pcs. Identically round up to 5 products.

Therefore, the area of ​​the doorway corresponds to an area of ​​10x5 = 50 pcs. tiles that need to be subtracted from total number for walls: 1232–50 = 1182 pieces.

Piece-by-piece calculation of ceramics for the floor

Let's calculate how many 20x20 cm format products will be required to cover a floor with dimensions of 421x234 cm:

• length 421 cm: 20 cm = 21.05 ≈ 21 pcs.;
• wide 234 cm: 20 cm = 11.7 ≈ 12 pcs.

Multiplying these values ​​gives the number of tiles per floor in pieces:

• 21 x 12 = 252 products.

Calculation of ceramic consumption for complex artistic decoration

If it is decided to make the decoration of the bathroom exclusive, the calculation of ceramics is done in a combined way - by the meter and by the piece. On horizontal and vertical surfaces, subject to registration, you need to make markings according to a pre-developed sketch map of the cladding. At this point, usually required types ceramics are already scheduled for purchase, and the format of the facing material with which the bathroom will be finished is known.

The marking is carried out with construction chalk; it begins with areas of the main plan that will be occupied by artistic panels and ornaments, the trimming of which is not allowed for aesthetic reasons. How many tiles are needed to cover such surfaces is easy to calculate individually.

Then they calculate the consumption of tiles for the frieze (if available on the sketch map) and cladding under the background for the panel. How much material is needed for laying the frieze can also be calculated by the piece method.

The choice of method for calculating the amount of ceramics when decorating the main background depends on the cost of the material, since not everyone plans to purchase surplus expensive tiles.

Results

The accuracy of calculating ceramic consumption when decorating a bathroom depends on the pricing policy. If after finishing the work there is a meter or two of facing material left, do not rush to call it a calculation error. This surplus will be indispensable for unforeseen spot repairs of the cladding. It is much worse when there is not enough material, and this type is no longer available for sale.

In order to calculate the amount of tiles for the bathroom, you first need to decide on the following questions:

• What type of installation will you use;
• Which color scheme you plan to apply;
• Will it be necessary to adjust the drawing;
• Will you lay only tiles on the walls or add decorative elements to the decoration?

Selecting the installation type

Floor

When working with flooring material The following types of installation are commonly used:

1. standard - when the edges of the tiles are laid along the walls;
2. diagonal – the edges are laid at an angle of 45 degrees;
3. diagonal checkerboard - when laying ceramics of different colors, they alternate.

Walls

When laying wall ceramics, you can choose the following types of cladding:

1. ordinary “straight” - when the elements are laid parallel to the floor;
2. regular with borders (one wide or narrow and wide, alternating);
3. diagonal;
4. checkerboard (regular direction or diagonal).

The choice of laying type is important, because with a diagonal direction, material consumption increases, because you will have to do a lot of trimming of the corners of the tiles to fit from the center to the corners of the walls.

When fitting to a pattern, you will also have to do a lot of trimming of the edges.

And it is also necessary to take into account that it is better to make the joints of the first rows away from the walls so that possible unevenness of the wall is not noticeable.

General calculation rules

Exist general rules How to correctly calculate the amount of tiles, whether for the bathroom or for other rooms where you decide to lay tiles.

• measure (in centimeters) the length and height of each wall on which you will lay tiles, and the length and width of the floor;
• from the dimensions of the wall in which it is installed Entrance door(or which has a bathtub) subtract the dimensions of this door (bath);
• decide on the size of the plates that you will lay (on the floor - 30x30, 33x33, 40x40 cm, etc.; facing - 20x30, 25x33 cm, etc.);
• Preliminarily calculate the result in square meters, and to clarify it you will need to count the number of tiles individually.

Moreover, keep in mind that the required amount of building materials must be immediately increased by 10%, because such a reserve will be required for trimming at the edges of the walls, in case of careless damage to the tiles or cosmetic repairs some section of the wall (floor) in the future.

When calculating the number of tiles, it is better to immediately do without an online program, because no matter how perfect it is, it still allows for errors. For example, it does not take into account the width of the seams between the rows, and its postscript still recommends checking all the results manually.

Laying tiles on the floor: calculation example

In order to make a specific calculation required for laying on the floor, we take the following data as the initial data:

1. Floor width – 150 cm
2. Length – 170 cm
3. Product size – 33x33 cm

Standard installation, tiles of the same color

• To find out how many tiles you need, first divide the width of the floor (150 cm) by its side (33 cm), we get the result - 4.54 (the number of tiles in one row in width), round to the nearest whole - 5 pieces.
• Now let’s calculate how many such rows are needed along the length of the bathroom: divide 170 cm by 33 cm, we get 5.15 rows, round up to 6.
• Next, we multiply 5 tiles in one row by 6 rows, we get 30 pieces. We add 2-3 in reserve, and that means we will buy 33 ceramic tiles.

If the calculation of the number of tiles had been made not by piece, but by floor area, then a serious mistake would have been made. Floor area – 1.70m x 1.50m = 2.55 sq.m, divided by the area of ​​one tile 0.33m x 0.33m = 0.11 sq.m, we get 24 (rounded) pieces. That is, 6 tiles (plus extra) would not be enough for the floor. After all, the piece count actually took into account the cutting of the plates during laying.

Bathroom wall cladding

• 270 cm (wall height) divided by 30 cm (tile height) = 9 elements in one row in height.
• 150 cm (surface width) divided by 20 cm (product width) = 7.5 – round up = 8 pieces in width.
• We multiply 9 by 8, we get - 72 units measuring 30x20 cm are needed for one wall 150 cm wide.
• Using similar calculations for a wall 170 cm long, we get the result - 81 tiles.

Taking into account the doorway

To calculate the amount of tiles required for cladding the wall in which the door is installed, it is necessary to subtract the amount that corresponds to the dimensions of the doorway from the number of elements for the opposite wall.

For example, divide 200 cm (the height of the doorway) by 30 cm (the height of the tiles), we get 6.7 - round down = 6 pieces in height; Divide 70 cm (the width of the opening) by 20 cm (the width of the product), we get 3.5 - round down = 3 pieces in width. We multiply 6 by 3, we get 18 pieces, which we subtract from (for example) 81, we get 63 pieces.

If you will completely cover the wall next to which the bathtub will be installed, then it is easy to calculate the number of tiles on it. If you do not plan to tile the space occupied by the bathroom, then the calculation for this wall is carried out similarly to the calculation for the wall with a door.

Calculating the amount of grout

After completion of the installation work, the joints are grouted. To do this, use grout that matches the color of the main color of the coating, or a contrasting one (white for black tiles, etc.).

To calculate the amount of grout for tiles, you need to know the volume of space to be filled. The seam width is recommended from 1.5 to 3 mm. To the joint depth, approximately equal to the thickness of the tile, you need to apply a coefficient of 1.5, which will take into account material shrinkage, humidity, etc.

To calculate the volume of grout, divide half the perimeter of 1 tile by its area and multiply by the thickness. Multiply the result by the width of the seam and by 1.5 (coefficient). The result will be the mass (in kg) of grout required for 1 sq.m of coverage. For example, with a joint width of 2-3 mm and a tile area of ​​0.04 sq.m, one kilogram of grout is enough for 3.5 sq.m.

Let's sum it up

As a conclusion, we can say that determining the area for laying tiles is not always effective and accurate, especially for small rooms. Apply in small rooms The calculation formula is also too complicated and impractical. It is better to make piece by piece calculations.

In the above examples, for simplicity of calculation and understanding of its very principle, the dimensions were taken as the initial data standard apartment and single-color ceramics without decoration or borders. These examples are quite enough to use the described rules to calculate the required amount of tiles for different colors, when installing curbs, etc.

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Discussion:

Denis said:

The commentators are amazing. You really had no idea how to count the number of pieces without this article? Unfortunately, the article did not touch on the topic: what size tile to choose, which wall to use as a base, so that you don’t have to cut pieces.

Sergey said:

Whoever wrote the article must be a genius. I could not even imagine that everything is so simple! I just got around to renovating my bathroom and thought I couldn’t handle it at all. Well, not my profile at all. It turned out that everything was just like that! Now I can check with people at hardware stores to see if they are trying to sell me a lot more tiles than I really need. This information really turned out to be very useful and timely.

Konstantin said:

For the most accurate calculation, so that there is no extra costs on the material, first decide on the choice of tiles. Knowing its size, it will be mathematically simple to calculate exact amount tiles on a specific surface, which will save your waste. Also, do not forget to take into account and discard when calculating the tile joint. Since the tiles do not fit joint to joint, and when laid under the “crosses” there remains a gap of 2 to 5 mm.

Plitkin said:

The calculations for the bathroom in the comments are not entirely correct. Because modern tiles carried out in the following sizes - for the floor 30x30, for walls 20x3 0, etc. Therefore it should be calculated like this:
Floor length 2.50m. - these are 8 rows of 30 cm = 2.40 + 10 cm. pruning
width 1m is 3 rows + 10cm. trimming, total: 8 x 3 = 24 pcs + trimming 8+4 = 12 divided by 2 (the middle will most likely have to be thrown out) = 6 pcs.
30 pcs per floor + 4 pcs stock.
Walls - width 2.5+2.5+1+1-0.75 (doors)=625 mm. – 32 rows of 20cm tiles.
height 2.5 x 30 cm. = 8.5 rows
32 x 8.5 = 272 pcs.