There is a lot of talk about the fact that they have a lot of advantages. Characteristics The material under consideration is the correctness of form and usefulness for the general living space. That is why the most important component for a correctly built house is a normalized calculation of the amount of material required. You can calculate the amount of timber per house yourself, without consulting specialists.
Of course, you should not avoid the advice of professionals, as they will be able to establish indicators in a short time and with incredible accuracy. To make calculations correctly, you need to determine the required volumes and find out how many components you need to take per square meter.
Thanks to the final results obtained, you can easily navigate the price range and future expenses.
Calculation of the quantity of materials
To make the calculation process more convenient, you need to use some list of simple tools:
- Regular pencil;
- A piece of paper;
- Calculator;
- Roulette.
It is important to know that the indicators given in this article are approximate. Therefore, for specific construction it is worth using your own data.
The most accurate pictures are compiled during the planning period and the availability of a final design for the future structure.
- Measuring the entire perimeter of the future building;
- Multiplying the perimeter by the floor height of the house;
- Multiplying the purchased numbers by the thickness of the material used;
- The resulting total number of cubes is the indicator necessary for the construction.
If, in addition to the walls, construction is planned internal partitions, it is necessary to take this factor into account when calculating. If necessary, obtain indicators not in cubic meters, they can be easily converted into units.
The specific moment is determined by dividing the total volume by the volume of a unit of production.
Counting example
Suppose you need to install a one-story structure with dimensions of five by seven cubic meters. In addition to this, you need to install a partition together with. The total ceiling height is equal to three meters. As for the pediment, it also consists of direct timber.
When performing the activity, a tree with a cross-section of 150 * 150 millimeters is used. In this case, the calculations will be as follows:
- 33 meters/(5+7)*2+5 – this is the immediate perimeter together with partitions;
- 33*3*0.15 = 15 square meters - these are the total volumes of the wall surfaces of the first floor;
- 5*3*0.15=2.25 square meters – pediment volumes.
Having received all the above indicators, it is necessary to summarize. In the case under consideration, it is shown that 17.25 square meters of material are required for wall surfaces.
This is all considering window openings, doorways, beams and, of course, floors. It is important to remember that components should be purchased with a small margin.
To summarize, the total cubic footage is equal to 25 square meters.
Dimensions of required materials
Quite significant parameters are thermal conductivity properties and, naturally, thickness. When producing a summer house or cottage necessary for regular living there, it is better to use materials of different thicknesses.
In case of summer country house width and thickness, in principle, have no special significance. Here it is possible to use materials with a cross-section of 100 * 100 millimeters. In the case of a cottage, you should pay attention to beams with a section width of more than 150 millimeters. Of course, additional thermal insulation wall openings.
The specific number of elements required for the construction process depends on the thickness parameters. If you want to save on the purchased material, you need to remember about the not entirely high-quality thermal effect obtained in the future.
To build an insulated building, you need to use timber with a thickness of approximately fifty centimeters.
A similar result can be obtained when using sections of 150 * 150 millimeters, as well as insulation of ten or fifteen centimeters.
When carrying out construction work on the construction of a residential building, a specialist must perform a large number of different tasks, one of which is: drawing up and calculating the estimated cost before the final finishing of the premises of a residential building. It is mandatory to calculate the required amount of various building materials, which is quite difficult to do. Therefore, such knowledge - how many boards are in a cube - is very important for a specialist who is engaged in the construction of a residential building and wants to complete the work as efficiently and quickly as possible.
Buying club: existing types of boards
To calculate exactly how many board pieces are in a cube, you will need to know not only what exactly a board cube means, but it is worth understanding important point that exist different kinds boards and what is possible to purchase on modern market for performing various construction works. It should be noted that the cube of almost all materials, regardless of the type of material, is calculated in the same way, that is, according to one specific method. The types of boards have no influence on the calculation of the cubic capacity of this building material.
Non-grooved types of lumber are: timber, various edged boards, as well as unedged boards (they are an exception when calculating cubic capacity, because this process occurs a little differently). Tongue-and-groove types (which have special grooves for making joints) include: modern lining, blockhouse, flooring material, as well as imitation of natural timber. When you choose a tongue-and-groove type of building material for purchase, then you will need to pay attention to the fact that when making calculations, only the working width of the board without a tenon is used. If we talk about a blockhouse (imitation log), then when calculating the cubic capacity, only the thickness at its highest point is taken.
How many boards are in 1 cube: performing the calculation
Any person, even from his school days, understands how cubic capacity is calculated. For this procedure, it is necessary to calculate quantities such as: length, width and height. A similar principle is used to calculate the cubic capacity of 1 board. When performing such calculations, it is recommended to convert all available values into meters. The cubic capacity of 1 board, which has a cross-section of 150x20 mm. and a length of 6 m, is calculated as follows: 0.15 multiplied by 0.02 and 6, so that the cubic capacity of this board will be 0.018 cubic meters.
Let's apply the volume formula V= L*h*b (where L is length, h is height, b is width).
L= 6.0; h= 0.02; b= 0.15.
Thus, V= 6.0*0.02*0.15 = 0.018 m3.
To determine how many boards are in one cube: divide 1 m3 by cubic capacity (the volume of one board).
1 m 3 / V = N pcs.
1 m 3 / 0.018 m 3 = 55.55 pcs.
Thus, the number of boards in one cube is 55.5 pieces.
Finding out the cost of a certain type of board when the values of its volume is known is quite easy: 0.018 multiplied by the price of 1 cubic meter. When 1 cube of a certain type of board costs, for example, 5,500 rubles, then the cost will be 99 rubles. At this point in the calculation, there is some trick of sellers and managers in construction stores, because the cubic capacity of the material is rounded to some integer values.
Such rounding can lead to such a moment that the price of 1 board (when 1 cube costs 5500) will be completely different values. In addition to all this, it should be noted that various boards for construction, which have a nominal length of 6 meters, the actual length is 6.1 - 6.2 m, which is not taken into account when selling this building material. This also applies to the purchase of a significant number of boards. This can be seen quite clearly if we use a 150x20 mm board as an example. The number of boards in a cube is a value of 55.5 pcs. But, in a cube they count 55 pieces, which when performing the calculation will have a value of 0.99 cubic meters. In fact, it follows from this that the overpayment for 1 cubic meter of this popular building material can amount to 1% of the real price. For example, 5500 instead of 4995 rubles.
To calculate the cubic capacity for a continuous type of board, slightly different methods are used. When we are talking about buying 1 board, then measuring its thickness, as well as the total length, is carried out in the same way as when choosing edged building material. In this case, the average width is taken for calculations - between a large value and a small one.
For example, when the width of the board at one end is 25 cm, and at the other 20, then the average value will be approximately 22 centimeters. When it is necessary to calculate the volume of a significant number of similar boards for construction, then you will need to lay them out so that the wide one does not differ from the narrow one, more than 10 cm. The main length of this material in the laid out stack should be approximately the same. After this, using a regular tape measure, an accurate measurement is made of the height of the entire existing stack of boards, and the width is measured (approximately in the very middle). The result obtained will then need to be multiplied by a special coefficient, amounting to a value from 0.07 to 0.09, directly dependent on the existing air gap.
How many boards are in 1 cube: special tables
To calculate the exact number of boards of a certain width and length in 1 cubic meter, various tables are used. Below are several such specialized tables, which indicate the cubic capacity of the common and in demand types of this material today. It is possible to calculate the volume of various boards of different sizes, for example, material for erecting a fence on your site, using the existing formula presented above.
Table of the amount of edged boards in 1 cubic meter
| Board size | Volume of 1st board (m 3) | Number of boards in 1m 3 (pcs.) | Number of square meters in 1m2 |
|---|---|---|---|
| Twenty | |||
| Board 20x100x6000 | 0.012 m 3 | 83 pcs. | 50 m2 |
| Board 20x120x6000 | 0.0144 m 3 | 69 pcs. | 50 m2 |
| Board 20x150x6000 | 0.018 m 3 | 55 pcs. | 50 m2 |
| Board 20x180x6000 | 0.0216 m 3 | 46 pcs. | 50 m2 |
| Board 20x200x6000 | 0.024 m 3 | 41 pcs. | 50 m2 |
| Board 20x250x6000 | 0.03 m 3 | 33 pcs. | 50 m2 |
| Twenty-five | |||
| Board 25x100x6000 | 0.015 m 3 | 67 pcs. | 40 m2 |
| Board 25x120x6000 | 0.018 m 3 | 55 pcs. | 40 m2 |
| Board 25x150x6000 | 0.0225 m 3 | 44 pcs. | 40 m2 |
| Board 25x180x6000 | 0.027 m 3 | 37 pcs. | 40 m2 |
| Board 25x200x6000 | 0.03 m 3 | 33 pcs. | 40 m2 |
| Board 25x250x6000 | 0.0375 m 3 | 26 pcs. | 40 m2 |
| Thirty | |||
| Board 30x100x6000 | 0.018 m 3 | 55 pcs. | 33 m2 |
| Board 30x120x6000 | 0.0216 m 3 | 46 pcs. | 33 m2 |
| Board 30x150x6000 | 0.027 m 3 | 37 pcs. | 33 m2 |
| Board 30x180x6000 | 0.0324 m 3 | 30 pcs. | 33 m2 |
| Board 30x200x6000 | 0.036 m 3 | 27 pcs. | 33 m2 |
| Board 30x250x6000 | 0.045 m 3 | 22 pcs. | 33 m2 |
| Thirty-two | |||
| Board 32x100x6000 | 0.0192 m 3 | 52 pcs. | 31 m2 |
| Board 32x120x6000 | 0.023 m 3 | 43 pcs. | 31 m2 |
| Board 32x150x6000 | 0.0288 m3 | 34 pcs. | 31 m2 |
| Board 32x180x6000 | 0.0346 m 3 | 28 pcs. | 31 m2 |
| Board 32x200x6000 | 0.0384 m 3 | 26 pcs. | 31 m2 |
| Board 32x250x6000 | 0.048 m 3 | 20 pcs. | 31 m2 |
| Sorokovka | |||
| Board 40x100x6000 | 0.024 m 3 | 41 pcs. | 25 m2 |
| Board 40x120x6000 | 0.0288 m3 | 34 pcs. | 25 m2 |
| Board 40x150x6000 | 0.036 m 3 | 27 pcs. | 25 m2 |
| Board 40x180x6000 | 0.0432 m 3 | 23 pcs. | 25 m2 |
| Board 40x200x6000 | 0.048 m 3 | 20 pcs. | 25 m2 |
| Board 40x250x6000 | 0.06 m 3 | 16 pcs. | 25 m2 |
| Fifty | |||
| Board 50x100x6000 | 0.03 m 3 | 33 pcs. | 20 m2 |
| Board 50x120x6000 | 0.036 m 3 | 27 pcs. | 20 m2 |
| Board 50x150x6000 | 0.045 m 3 | 22 pcs. | 20 m2 |
| Board 50x180x6000 | 0.054 m 3 | 18 pcs. | 20 m2 |
| Board 50x200x6000 | 0.06 m 3 | 16 pcs. | 20 m2 |
| Board 50x250x6000 | 0.075 m 3 | 13 pcs. | 20 m2 |
Table of the amount of timber in 1 cubic meter
| Beam size | Volume of 1st piece (m³) | Quantity of timber in 1m³ (pcs.) |
|---|---|---|
| 100×100×6000 | 0.06 m 3 | 16 pcs. |
| 100×150×6000 | 0.09 m 3 | 11 pcs. |
| 150×150×6000 | 0.135 m 3 | 7 pcs. |
| 100×180×6000 | 0.108 m 3 | 9 pcs. |
| 150×180×6000 | 0.162 m 3 | 6 pcs. |
| 180×180×6000 | 0.1944 m 3 | 5 pieces. |
| 100×200×6000 | 0.12 m 3 | 8 pcs. |
| 150×200×6000 | 0.18 m 3 | 5.5 pcs. |
| 180×200×6000 | 0.216 m 3 | 4.5 pcs. |
| 200×200×6000 | 0.24 m 3 | 4 things. |
| 250×200×6000 | 0.3 m 3 | 3 pcs. |
Table of the amount of unedged boards in 1 cubic meter
Before starting to build a house made of timber, many consumers ask themselves: how much timber is needed for the construction of the planned structure. To answer this question you can go two ways:
- Use the beam calculation calculator;
- Read the article below about calculation of the amount of timber which will be needed to build a house.
And if everything is more or less clear with a calculator, then doing it yourself is much more difficult. Let's look into this issue.
Factors influencing the amount of timber required to build a house.
The main thing to consider when calculating the amount of timber per house is:
- What type of timber will be used in construction;
- How much timber do we need?
- How many units of timber are in 1 cubic meter;
- Features of the project of a house made of timber or a cottage.
Calculation of construction timber in cubic meters.
And so, how calculate the amount of timber in 1 cubic meter simple method? It should be noted that the example below is not exact. To make a more accurate calculation, you need to have a project of the future house.
To calculate the amount of timber in 1 m 3 you need:
- Calculate the perimeter of the building;
- Multiply the perimeter by the height;
- The product of the perimeter and height must be multiplied by the thickness of the product.
For our case, the formula will look like this: V = h*b*l = 0.15 * 0.15 *6 = 0.135 m3,
- h is the height of the beam;
- b- width;
- l- length.
Let's find out how many units of lumber are in 1 cube as follows: 1/0.135 = 7.41 pieces.
After carrying out all the above calculations, we will get the result of the number of cubes of timber required to construct the building.
To calculate timber which will be needed for finishing interior walls, we use a similar method. let's consider specific example, how to calculate the amount of timber for a bathhouse 5 * 10 meters, 3 meters high.
Let us conditionally determine that during construction the size 150 * 150 mm will be used.
- (5 m - width + 10 m length) × 2 = 30 m - perimeter of the building.
- 30 perimeter × 3 height = 90 m 2 - wall area.
- 90 area × 0.15 material thickness = 13.5 m 3 - needed to build a box from a 5 × 10 beam 3 m high.
Like this in a simple way we calculated the amount of timber for the walls, which is 13.5 m3. But, you need to take into account that due to the presence of window and door openings, the amount of material used will be less than calculated.
Often craftsmen do not take this point into account; it is believed that it would be even better to add about 20% in reserve, in the end we will get: 13.5 + 20% = 16.2 m 3 timber is needed for a building 5 * 10 m.
Features of timber that must be taken into account when calculating.
When building a house from timber, the first step is to lay the crown, which should be slightly thicker than the main beam. The first crown is made of thicker timber; later the weight of the whole house will put pressure on it, so it is additionally recommended to treat it with machine oil or an antiseptic.
In the calculation described above, this nuance was not taken into account; it must be calculated separately.
Calculation of timber in units.
After you have calculated the amount of timber in m3, you can easily find out how much timber will be needed in units (pieces).
Let's look at the table of common sizes of this product 6m long:
Table of the amount of timber in 1 m 3 for calculating timber for a house.
|
Section * timber length |
Volume 1 piece, m3. |
Quantity of timber in 1 m3, pcs. |
|---|---|---|
In the above example, where we indicated the cubic capacity of the timber for the bathhouse, we will carry out further calculations of the materials in pieces.
In order to calculate the amount of material per house in pieces, we carry out the following calculation; for this, the amount of 13.5 m3 must be divided by the cubic volume of the timber used, in our case it is equal, based on the table, to 0.135 m3: 13.5: 0.135 = 100 pieces.
If you correctly calculate the amount of timber in pieces, then when purchasing timber you will be able to control whether all the material is shipped to you by the seller.
Thickness and height of timber.
The material can have different thickness and height, the following are the main dimensions:
- 100*100 mm.
- 100*150 mm.
- 150*150 mm.
- 150*200 mm.
- 200*200 mm.
If everything is clear with height, the higher the beam, the fewer inter-crown seams, the faster the production construction works, and naturally, the number of pieces of timber for building a house decreases. But the width in this case is more important, especially when building for all-season living.
Attention: Sometimes timber manufacturers indicate the dimensions of the timber, which may differ from the real ones; for example, a timber of 150x150 mm actually has a size of 140x140 mm.
The consequences of purchasing such a beam will be very disastrous, if for a height of 3 meters you will need 20 pieces of timber measuring 150x150 mm, then for a size of 140x140 mm - 21 pieces and a half, and this is one and a half crown rows.
If you plan to live in the house all year round, then it is recommended to use timber with a thickness of 200 mm. It is also necessary to take care of the insulation of timber walls, the best option will be polystyrene or mineral wool 10 cm thick.
When constructing a bathhouse, it is advisable to use a material thickness of 150 mm; it is quite sufficient for short-term temperature maintenance. Well, if you decide to build country house For summer holiday, then in this case walls made of 100x100 mm timber will be just right.
Building a house always involves significant financial costs. However, to ensure that costs do not exceed the allotted limit, and that materials are purchased in sufficient quantities, it is necessary to calculate the cost of building a house made of timber.
Regardless of whether you plan to build a home on your own or will hire workers for this, you need to draw up an estimate. This is the basis of all work.
Formula for calculating timber consumption for load-bearing walls of a house
Calculation of timber for building a house is carried out according to the formula:
- the sum of the lengths of all the walls of the structure is calculated, not only external, but also internal - this is the perimeter;
- the perimeter is multiplied by the height of the house, excluding the pediment area (the facade of the building, limited by the roof slopes and cornice);
- the value obtained as a result should be multiplied by the thickness of the timber selected for construction.
The result is the number of cubes required to build a house. Usually limited to one, less often two floors.
It is convenient to consider the formula using a specific example:
Total: to build a house you will need 13.5 cubic meters of timber with a cross section of 150*150 mm. If there are more walls expected, then they are also taken into account in the calculations.
For the convenience of calculations and to facilitate the purchasing process, you can use the data below, with a length of 6 m:
|
Beam section |
PC. cubed |
Volume 1 pc. |
In order to correctly calculate the construction of a house made of timber, it is necessary to take into account a moment that cannot be avoided during individual construction - even the most trusted supplier may have several defective units in one batch. This must be taken into account when purchasing and purchase blanks with a small margin.
It is better to take products from the same batch, otherwise problems may arise during joining of elements due to different ways processing and its quality.
Stage two: material consumption for the roof frame
For a house made of timber, a rafter system is used - this is the load-bearing frame of the roof. Wood is a durable material, but it should not be overloaded so as not to provoke uneven shrinkage and destruction load-bearing walls.
Factors influencing the amount of material required for a roof frame
To ensure that the roof is not only beautiful, but also reliable, you cannot skimp on building materials. It is necessary to strictly follow the technology when constructing it yourself.
Frame wooden roof includes the following required elements:
- rafter legs, or just rafters;
- pediment, made of timber similar to load-bearing walls;
- logs (beams) - horizontally located beams, the base on which the floorboard is laid;
- Mauerlat - the thickest beam, located along the perimeter of the walls, designed to evenly distribute the weight of the roof frame;
- sheathing - attached to the rafters and serves as the basis for laying the roof.
SNiP 31-02 imposes a number of requirements on any roof, based on which the materials for building a house made of timber should be calculated. That is, in order for the frame to comply with the stated standards and protect the structure from snow, melt and rain water, not allow cold air to pass through, and be energy-saving, it is necessary to find out exactly how many blanks are required.
How to calculate the amount of building material for a frame: Mauerlat
The amount of material directly depends on the coverage area. As an example, consider a 6x6 house. For a reliable foundation, you will need a thick, strong beam with a cross-section of 150*100 mm or 150*150 mm. It is laid on 4 load-bearing walls, respectively, to build a mauerlat you need 4 beams of 6 m each.
Note! If the structure does not have internal load-bearing walls, then the distance between them should not exceed 8 m. If there is another support inside the house, then the distance increases to 14-16 m.
To calculate the amount of timber for a wall length exceeding 6 m, it is necessary to calculate the total footage of the perimeter:
For example: 6+6+9+9=30 m
30 m is the perimeter, divided by the length of one block.
30 m/6 m=5 pcs.
Total: to construct a mauerlat for the construction of 6x9 m, you need 5 bars of 6 m each.
Calculation of the amount of material for rafters and sheathing
The rafter system is the main support for roofing material, it protects it from wind and snow.
Calculation of material for the construction of a house made of timber, which will be used for the construction of rafters, is carried out according to the formula:
- The total load of snow and wind per square meter of roof - it is calculated on the basis of SNiP 2.01.07-85 “Loads and impacts”. For a slope with a slope angle of 45◦, a roof length of 6.5 m and a rafter length of 3.5 m, the load will be 226.3 kg/sq.m.
- The total load is 5148 kg. We multiply 6.5 by 3.5 and get 22.75 m - this is the surface area of \u200b\u200bone slope. Accordingly, 22.75*226.3=5148 kg.
- Now you need to find out the length of all the rafters and, therefore, how much timber you need to purchase for their construction. For this, based on the fact that one linear meter able to withstand 100 kg of weight, divide 5148 by 100, the result is 51.48 m - this is the minimum length of the rafters.
- The roof slope overhangs the wall by about 50 cm, so you need to buy 4 m of wood.
- It’s easy to calculate the number of pieces: 51.48/4 = 12.87, or more precisely 14, since they are arranged in pairs. That is, you need 7 pairs.
The instructions say that the distance between the rafters is equal to the number that is obtained if you divide the length of the roof by one less than the number of pairs of rafters: 6.5/6 = 1.08 m. The cross-section of the blanks is 100 * 150 mm or 150 * 150 mm.
The rafter system includes wooden sheathing. For it, boards about 2.5 cm thick are used. They are placed horizontally, that is, parallel to the ridge.
The width of the board should not exceed 15 cm. There are two installation methods, which will determine the amount of material purchased.
The first is continuous laying, when the distance does not exceed 1-2 cm and is discharged. Then the span can reach 10 or more centimeters. The more often the boards are laid, the stronger and warmer the structure, but at the same time, the more expensive it is.
It's easy to calculate the quantity. The lengths of the skate and board are measured. Next, divide the skate footage by the board footage. This helps to find out how many boards are needed for one strip.
If the width is 15 cm and the gap is 5, then divide the length of the slope by the number obtained as a result of addition. The total is the number of blanks in pieces.
Calculating the cost of building a house from timber is a very painstaking task; it is also necessary to take into account the fact that everything must be purchased with a small reserve in case of defects. Roofing consumption is calculated based on the roof surface area. This does not take into account natural openings - a place for a chimney pipe and an attic door, if one is included in the project.
Number of blanks for beams
Floors from wooden beams are most in demand in low-rise construction. They have a relatively low cost, they are easy and quick to make, wood is a fairly durable material, and is light in weight. It does not place significant loads on the foundation.
Only wood is used to cover the beams coniferous species, more often larch is the most durable and reliable material, able to withstand significant weight:
- resistant to temperature fluctuations;
- maintains stable geometry;
- almost no shrinkage.
Choose better than blanks, which have been dried in steam chambers and have a moisture content of no more than 14%. The aspect ratio should be 150*100 mm or 150*200 mm.
For correct design, to make the correct calculation of materials for building a house from timber, it is necessary to be guided by the span width. The larger the span, the more often beams are laid and their number will increase. For attic floor It is not necessary to place the workpieces too close to each other.
Here is a table that makes it easy to determine how many pieces you will need:
|
Span width |
Beam spacing |
Optimal workpiece cross-section |
This means that for a span of 4 m you need to buy 6 blanks for laying floor beams, taking into account a step of 1 m. That is, 4 pieces will be used to cover the span and 2 more for the edges, directly next to the walls. The price depends on the length of the beam.
Stage three: number of floorboards
Before you start making calculations for purchasing a floorboard, you need to decide on its parameters.
- The most optimal lengths are 4, 4.5 and 6 m.
- The thickness is available in the following sizes: 30 mm, 25 mm and 32 mm.
- Standard widths are 100 mm and 105 mm.
If you want to make a floor from whole boards, then it is advisable to reduce the amount of waste.
Calculation of material for building a house from timber is made based on the length and width of the covered area. And also how the board will be laid - along or across.
The calculations are quite simple. If you know the parameters of the workpieces, you can determine usable area, it is 5-7 mm less than the actual one due to the tongue.
Most often, manufacturers make boards 6 m long. It is also necessary to take into account the possible amount of waste that cannot be avoided.
Calculations are made as follows:
- in advance known area living space is divided by the area of one board, taking into account only the useful one - this is the amount required for installation;
- when the room has parameters different from 6 m, it is important to know the amount of intact material. To do this, the width of the room is divided by the working width of the floorboard.
Based on the information received, you can simply find out approximately how much it will cost to build a house made of timber. It is also necessary to take into account Consumables: insulation, roofing material, additional fasteners. Their number depends on the design of the house, the area and other factors.
Conclusion
The video in this article will clearly help you understand these issues.
Before purchasing any building material, it is necessary to determine the required quantity as accurately as possible, otherwise you may lose some amount due to remaining surpluses or the need for additional purchases, as well as the unaccounted for possibility of deception on the part of unscrupulous sellers. Beams, logs, boards and similar products made of wood, as you know, is sold in cubic meters, which means you need to know all the details of the calculations for determining the volume of these materials, as well as converting the required number of pieces into cubes and back. And in the case of purchasing timber for building a house, when calculating the required amount of this building material, it is also necessary to take into account the design and features of the future building.
Basic calculations - determining volume and converting from pieces to cubes and back
It is very simple to calculate the cubic capacity of timber, boards and similar lumber. To do this, you need to know the thickness, width (height) and length of the product. And, as you know from a school textbook on geometry, you need to multiply these dimensions:
V = T ∙ H ∙ L, where
V – volume of timber, m3;
T – thickness;
H – width;
L – length.
Dimensions before calculation should be given in one unit of measurement: mm, cm or m. It is better in meters, so as not to have to convert from mm 3 or cm 3 to m 3 later.
Timber size table
For example, let’s calculate the cubic capacity of a beam of 150x200. These dimensions, as you know, are indicated in mm. That is, the thickness of the product is 0.15 m and the width is 0.2 m. The standard length of timber and boards is 6 m (sometimes also indicated in mm - 6000). Or maybe another. But for example, let’s take exactly 6 m. Then the volume of this lumber is:
0.15 ∙ 0.2 ∙ 6 = 0.18 m 3.
Now you can convert the required quantity (in pieces) of this product into cubes. Let's say 49 pieces are required:
0.18 ∙ 49 = 8.82 m3.
Knowing the volume of one product, you can also calculate the cube of timber, that is, determine how many units (pieces) there are in 1 m3. To do this, you need to divide 1 cube by the cubic capacity of one product, already calculated or taken from reference tables (in the example under consideration - 0.18 m3):
1 / 0.18 = 5.55555... pcs.
The amount of this type of timber is calculated in the same way for any volume.
Nuances of calculations - how not to make mistakes and not be deceived
As follows from the above methods and calculation examples, it is very easy to calculate the required volume of timber in pieces or cubic meters. However, one must always remember that 1 cubic meter does not contain a whole number of these products. For the example given with dimensions 150x200, length 6 m - 5.55555... pcs. Unscrupulous, most often timber retailers, cleverly take advantage of this.
For example, you need 1 cube of this material from the example. The seller, of course, sells 5 products, but charges the amount for a whole cubic meter. The overpayment will be the cost of half a beam.
Let’s say that to build a house you need the same 49 beams from the example. And if the seller calculates according to the following scheme, then he will have to significantly overpay for the timber received:
- 1 cube – 5 products 150x200, 6 m long;
- 49/5 = 9.8 cubic meters payable.
This is a scam pure water for 5 units of timber. They are superfluous and unnecessary, but will be paid for but not received. In the calculation examples above, the data of 49 products has already been converted into cubes - this is 8.82 m 3. That is, a “particularly enterprising” seller will deceive an inattentive buyer by:
9.8 – 8.82 = 0.98 m 3 timber,
which is 0.98/0.18 = 5.44444... pcs. of this lumber (0.18 – the volume of one product calculated above).
Therefore, the most correct thing would be to calculate in advance exactly the number of units (pieces) of material, and only then, using this data and the dimensions of the timber or board, calculate their actual cubic capacity.
That is, in the case of purchasing one cubic meter in the example above, you must first decide how many beams you really need to take - 5 or 6. And then we calculate their cubic capacity:
0.15 ∙ 0.2 ∙ 6 ∙ 5 (or 6 pcs.) = 0.9 (or 1.08) m 3.
And for 49 units of this timber:
0.15 ∙ 0.2 ∙ 6 ∙ 49 = 8.82 m 3.
Then you will have to pay exactly for these 0.9 (1.08) or 8.82 cubes, receiving exactly 5 (6) or 49 products. Moreover, both the quantity in pieces and the volume in m3 must be indicated in the invoice for the timber sold by the seller.
Other features of calculating lumber cubic capacity
Another one important feature, which you should know for correct calculation cubic capacity of timber or boards when purchasing them. The actual length of lumber is usually always slightly longer than the standard or declared by the manufacturer of this product. So, instead of 6 m, the average length of the timber in question is, as a rule, 6.05 m. This is due to the fact that the ends of the lumber are not processed after cutting, which is why they may turn out to be uneven, go at angles, and be different, or simply be dirty. Of course, you don’t have to pay for these 5 cm. But some cunning sellers, although quite rarely, still try to take even this into account when calculating cubic meters, which is pure deception.
And regarding calculations for tongue and groove and profiled timber. The presence of tenons, grooves, and other protruding or chiseled places should not be confusing. Calculating the cubic capacity of such materials is no different from determining the volume of ordinary products that are even on all sides. For tongue-and-groove and profiled lumber, the rule is that only the main part (working width) of the product is measured and taken into account, and all structurally necessary and/or decorative elements are not taken into account in calculations. This provision applies to absolutely all types of timber.
Purchase of large volumes of materials - calculation of folded and dense cubic meters
When to purchase a large number of timber, their cubic capacity is calculated somewhat differently than discussed above. For example, timber and boards are needed to build an impressive, spacious house, as well as various other outbuildings near it. At the same time, the necessary lumber will certainly be available different sizes V cross section and length. Measuring and calculating each type of required material for such purchase volumes is an activity that can take more than one day.
For such cases, there is a specific calculation method. It is based on two important concepts:
- 1. Dense cubic meter of wood. This is the name given to a volume occupied only by wood and without voids or gaps in it. It is determined by measuring individual timber pieces individually, and then subsequently calculating their total cubic capacity.
- 2. Folded cubic meter. This is the name given to the volume occupied by lumber stacked as densely as possible and having voids, as well as gaps between individual wood products. It is determined by measuring the stack and then multiplying the dimensions of the latter. Moreover, in such a package the main amount of material should have approximately the same length, and the remaining products can be shorter, but not longer. It is allowed to have short lumber in the stacks, which should be stacked tightly one after another.
In order to quickly calculate the large volume of required purchased lumber, which has already been prepared and stored in the form of a stack, the latter is first measured and then its cubic capacity is calculated. This will calculate the fold cubic capacity. Then its value must be multiplied by a special conversion factor. The result will be a volume of only wood (a dense cubic meter), that is, exactly those materials that are purchased and will be paid for.
The value of the conversion factor is regulated by a number of standards for lumber: GOST 6782.2-75, 6782.1-75, 6564-84, OST 13-24-86 and others. For timber and boards, depending on their moisture content and the type of wood from which they are made, the value is in the range of 0.74–0.82.
We calculate the required cubic capacity of timber for building a house
- Height external walls, measured from the foundation level. Let's denote it as H.
- The height of the internal partition walls, if they exist and should be made of timber.
- Length of external and internal walls.
- Number and length of beams used in rafter system, as floor beams and, as well as in its other structures - if provided for by the project.
Then we select the thickness of the material for each of the above structural elements. For external and internal load-bearing walls, depending on the purpose of the house being built and the region where it is being built. For non-load-bearing partitions - at your own discretion. The base (lowest) crown of external walls is usually slightly thicker than the rest of the timber for them. For other structural elements, the thickness of the material is selected based on its operating conditions, as well as the required strength of the structures in which it is used. In a well-drafted project, by the way, the thickness of the timber used for the walls, plinth crown, and other structures of the building should already be indicated.
Now all that remains is pure arithmetic. First, we calculate the perimeter of the house - add up the length of all its external wall structures. For a simple rectangular or square structure, you just need to add its width and length, and multiply the resulting value by 2. Then we calculate the cubic capacity of the base crown:
V C = T C ∙ Z C ∙ I, where
V C – total cubic capacity of basement lumber, m 3;
T Ts – thickness of the base product, m;
Z T – its width (height), m;
I – perimeter of external walls, m.
We calculate the remaining height of the external walls, m:
h = H – Z Ts, where
H – total height, m.
We calculate the area of external wall structures without a plinth, m2:
If the thickness of the material of the base crown is the same as that of the entire wall, then the area of the latter, m 2:
We calculate the area of the internal walls, the thickness of the lumber of which is the same as that of the external ones, m2:
S B1 = H B ∙ L B1, where
H В – height of internal walls, m;
L B1 – total (total) length of internal walls, the material thickness of which is the same as the external ones, m.
We calculate the area of the internal walls, the thickness of which is different, m2:
S B2 = H B ∙ L B2, where
L B2 - total length of internal walls, the thickness of the material is different, m.
We calculate the cubic capacity of the main lumber - for external walls and internal partitions made of the same timber, m 3:
V S = (S H + S B1) ∙ Z S, where
Z S – selected product thickness, m.
We determine the volume of material for internal partitions from other timber, m3:
V B = S B2 ∙ Z V, where
Z B is the selected material thickness for these partitions, m.
We divide the results obtained (V C, V S and V B) by the length of the purchased lumber and its selected width (height). You will get the amount of material in pieces. We round this value to a whole value, and then recalculate V C, V S and V B, as described in the second chapter.
To save on lumber, you should calculate the total areas of window, door and other openings for the corresponding walls. Then their values must be subtracted from S H, S B1 and S B2, respectively. After this, we calculate V S and V B using the same formulas. Then we increase the obtained values by 10–20% - so that there is a reserve just in case.
The cubic capacity of the timber for the remaining elements of the house in which it is used is calculated even easier. Its total length is calculated and multiplied by the thickness and width selected for the material.