All about the rounded bar

Ordinary (untreated) logs have a conical shape, which is completely inconvenient for construction. Once upon a time, houses were also erected from such material, but all the same it was necessary to trim the diameters of almost all the logs. Moreover, this had to be done manually, which delayed both the term of work and its cost. Now it is possible to align logs on a milling machine to almost the same diameter. Houses made of such material turn out to be smooth, smooth, reliable, with a glossy shine of logs.

A rounded beam is nothing more than a rounded log, which is also called calibrated. Rounding means that the log has been mechanically processed by a specially designed machine. As a result, the log became smooth, its shape acquired the correct cylindrical appearance, and the diameter was leveled off along its entire length. There can be no deviations in diameter. If they are found, it means that the processing was carried out in violation of the technology. Do not confuse rounded and profiled timber: they differ even in appearance. The first is with a round section, the second is with a rectangular or square section. A calibrated log always has only a cylindrical shape.

If the beam is calibrated in industrial volumes, then the deviation in the diameter of one log from another cannot exceed 4 mm, and this applies to the entire length. Only then will the structure turn out to be even, all the elements will be ideally fitted to each other, no additional processing is required. In the workshop, not only cylindering is performed, but also the application of bowls, grooves, grooves and everything that is necessary for the construction of a house or a bath on the timber. After completing the work, the structure is assembled in the likeness of the Lego constructor. Rounded timber with a standard diameter of 22-24 cm is the most suitable material for summer cottage construction. Houses from it are warm and durable.

Like any building material, calibrated timber has advantages and disadvantages. The advantages include the following properties:

• relatively low weight;
• high strength and reliability;
• environmental friendliness and pleasant microclimate in the house;
• ease of processing;
• high resistance to fungus and rot;
• low degree of shrinkage of the structure (maximum 3%);
• little cracking;
• long service life.

Several factors correspond to cons.

• Low fire resistance.
• When the frame is assembled, construction is suspended until the final shrinkage of the structure. This period ranges from 4 months to 1 year.
• If the timber is poorly dried, it can lead, and it will also crack strongly. To avoid this, you need to either build from a thermal log, which will cost much more, or "seat" the walls on metal threaded studs.
• A wooden structure (including timber) must be caulked periodically. The first time the structure is caulked directly during its assembly, the second - after complete shrinkage. For the third time, cracks and joints need to be caulked 2-3 years after the start of operation at home.
• It is required to treat each log with an antiseptic compound that protects the wood from decay, fungus and mold.

Rounded logs can be classified according to various parameters. For example, by the type of processing.

• Chopped type. The log acquires a cylindrical shape due to manual processing by means of a planer. The bowls are also cut with a plane. This is a very long and laborious process, but suitable for lovers of everything authentic Russian.
• Calibrated. Here, all cylindering work is carried out by a milling machine in production. In this case, the timber acquires an ideal geometric shape, the grooves and bowls are also located in the right places.

By the type of wood, logs are pine, spruce, cedar, larch, as well as oak, birch and others made from deciduous trees. It should be noted that coniferous logs have a special aroma and resinousness.

Depending on how the groove is located, calibrated logs are:

• with a longitudinal arrangement - the groove runs clearly in the center of the beam in the direction along the log;
• with a diagonal arrangement - a rare modification, but indispensable for the construction, for example, of a bay window;
• with a transverse arrangement - an ordinary bowl is hidden under this term.

A log can have:

• natural moisture - the moisture level can reach 22%, uniform drying is impossible due to the large size of the log. Bars of natural moisture are dried for 2 months, having previously sanded them and stacked in piles. Finally, such a bar dries up already in the assembled house.
• be dried (thermally modified) - such logs are dried in an airless space at high temperatures (up to 180-190 degrees Celsius). The thermal log has a humidity level of up to 20%. Due to the complex drying system, such a bar is more expensive. Due to difficult drying conditions, wood can acquire a noble dark color without any chemical attack.

Besides, the log differs depending on the type of profile:

• With a moon groove - more budgetary, however, during construction, you will have to constantly check the verticality of the structure and its elements. A house from a bar needs additional insulation and a large amount of airtight foam to seal up voids. But on the other hand, this type of timber has more ready-made models in which it is produced.
• Finnish profile - more expensive, while retaining heat better. Thanks to the mounting grooves, the assembly of the log house is much faster. You do not need to caulk at the same time.

• Beam with a diameter size from 160 to 180 mm good for the construction of small buildings in warm climates. It is widespread in the southern regions of the country for the construction of summer cottages, guest houses, terraces and verandas, as well as summer kitchens.
• Log size with diameter from 200 to 220 mm suitable for building a bathhouse or a country house with average heat saving properties. Such material is used in regions with an average climate.
• Bar diameter from 220 to 280 mm suitable for the construction of houses in any of the northern regions. However, in most cases, it will be necessary to additionally insulate the walls and attic floors. They are built from such a beam in the North and in Siberia.

The working height should not be forgotten either. This is another dimension that is important for the performance of the calibrated bar. Working height means how many crowns need to be folded in order for the wall to be of the desired height. The working height is calculated by measuring the segment "top of the groove - the upper point of the section of the bar". The working height also depends on what groove the log has. For example, a log with a diameter of 240 mm and a lunar groove has a working height of 208 mm, and with a Finnish one - 90 mm. All this is because the lunar groove is already Finnish. However, the lunar groove can be extended up to 20 mm.

When choosing a calibrated timber for construction, you need to pay attention to the following points.

• Logs from the same batch should not differ in their characteristics, that is, they should be from the same tree variety, have the same diameter and length.There may be deviations, but the minimum is 1-2 mm.
• Each bar must be marked in the same way;
• There should be no mechanical damage on any log. It is unacceptable for the material to have rot, mold, wormholes. If a log is declared thermally modified, it cannot be wet. In addition, there must be documents confirming the conditions for drying wood;