How to calculate the volume of timber for the house

18-05-2018

Building

When you order 1 m3 of sawn timber to build a house, you need to be well aware of this volume. In fact, this number is not very large. For example, a bar of 200x200x6000 will be about 4 pieces. It should be noted that sellers usually round off the volume, which with large orders may not be in your favor. In this case, when choosing the quantity of sawn timber, it is necessary to know how to calculate the volume of a bar for a house as accurately as possible.

Dimensions of the building

At the preliminary stage it is necessary to determine the size of the future house from a bar and a log. To do this, calculate:

the area of walls, window openings and doors;
step of cross-beams in the ceiling;
the height of the rafter;
the geometry of the gables, if they are made in the same style with the house.

In other words, the calculation of the volume of timber on the house implies a clear definition of where you want to apply it. In addition, you should immediately determine the material for construction.

Material

In this case, the industry offers three options:

plain;
profiled, can be made of simple or glued;
glued.

The first one is the cheapest sawn timber, but it has a number of drawbacks that can reduce the benefits to zero. Using a profiled bar makes it possible, even with minimal carpentry knowledge, to build a house. You will need only assembly instructions.

Plywood and larch glued timber resembles a “wooden stone” more, therefore it is often used in places where increased rigidity is required, but its price also exceeds previous versions. The first two sawn timber are “breathable”, i.e. make a wooden house a full ecological housing.

Today, bars of various dimensions are produced, but most often they choose the middle ground in (mm):

for the southern regions - 150x150;
for the middle band and higher - 200x200.

Tip: use just such a size. It meets the requirements of thermal conductivity in the region and is convenient for building the structure. In the case of its reduction, this may cause an increase in labor costs and materials used.

Payment

Rarely buy lumber by the piece. Therefore, when it is necessary to determine the required number of cubic meters of wood, you should use a simple calculator.

The overall size of the house is usually reflected in the plan, where there are also other basic parameters. How to calculate the volume of timber for a house will be described below.

In order to calculate the quantity, for example, for a wall with a height of 3 m and a length of 10 m, it is necessary to divide the height by the cross-section of timber in (mm):

If the timber 150x150 is selected - 3: 0.15 = 20 pcs .;
If the bar is selected 200x200 - 3: 0.20 = 15 pcs.

From the calculation it is clear that it will take 15 or 20 pieces of timber 10 m long. But, usually the maximum size is 6 m, so it would be more correct to say this:

With a cross section of 150x150 mm, you will need 20 pcs. - 6 m and 20 pcs. - 4m each;
With a cross section of 200x200 mm: 15 pcs. - 6 m and 15 pcs. - 4 m.

When using a simple bar, you can ignore the possible height of the insulation, since it is leveled by the shrinkage of the wooden profile.

In the end, it turns out that we need on one wall:

With a cross section of 150x150 mm on one wall - 4.5 m²;
With a section of 200x200 mm - 6 m².

Adding a basement crown - 2 pcs. (6 m + 4 m), it turns out that one wall has an area of 3 m², we need to:

Bars with a section of 150х150 mm - 42 pieces. (21 pieces on 6 m and 21 pieces on 4 m);
Bars with a section of 200х200 mm - 32 pieces. (16 pieces on 6 m and 16 pieces on 4 m).

The results should be multiplied by the number of walls and partitions in the future house. But, is it possible to save on wood and will it not affect the structure? To do this, remember that in almost every wall should be windows and doorways.

Wooden house with window and door openings

Advice: take a tape measure and measure out places for them, so as not to buy excess lumber.

For example, the door immediately saves 2 m.², and a window of 1.5 m2, will reduce costs by about 5%. They can be used for fastening rafters and attic floors. For interfloor lags, it is necessary to purchase a profile with sides of 7: 5, where the first figure indicates the height.

Simple calculation method

In the previous paragraphs, we obtained the result we needed for subsequent calculations, which showed how many wooden profiles are needed for construction. The next stage is the calculation of the total lumber.

For this there is a bar volume formula. It is quite simple and well known from school: V = h x b x l, where the height is “h”, width is “b”, length is “l”. So in (mm):

With a cross section of 150x150 and a length of 6000 - 0.135 m3;
With a cross section of 150x150 and a length of 4000 - 0.09 m3;
With a cross section of 200x200 and a length of 6000 - 0.24 m3;
With a cross section of 200x200 and a length of 4000 - 0.16 m3.

Then we determine the amount of lumber in 1 m³: 1 / 0.135 = 7.4, 1 / 0.24 = 4.16, Since none of the sellers will cut off the extra pieces, you have to buy 8 or 5.

But, you see, we need much more material than one cube, so the losses on such an amount will be minimal.

There is an even easier way, especially when you decide to build a house with your own hands. It is necessary to calculate as accurately as possible the surface area of the future home — multiply the perimeter by the height of the walls. After that, you should subtract the window and door openings or, if you were not going to save, you can leave it as it is.

The result is then multiplied by the thickness of the selected beam, while the basement rim is not taken into account. This calculation is less accurate, since many components are not taken into account.

Tip: use this method for utility rooms.

Conclusion

When building a wooden house, you need to know exactly the amount of lumber required. This will not only save money, but not stop the process. In the presented video in this article you will find additional information on this topic.