All about bar caulking

The profiled timber practically does not shrink, and the spike-groove connection allows you to perfectly fit the material to each other and use less insulation. Nevertheless, even a log house shrinks over time, which means the appearance of cracks and the need for caulking.

Under its own weight, the house sags over time, especially in the first year. As a result, gaps are formed between the crowns, which let the cold through, and drafts appear. The penetrating moisture exposes the wood to rot, mold and pests.

The tree itself suffers from the vagaries of the weather. The bars absorb moisture, swell and shrink when dry. Cracks may appear. The insulation laid during the construction of the house is also crumpled or pulled apart by birds over time.

Therefore, the caulking of the bar allows you to:

• improve thermal insulation;
• exclude the icing of the walls and the appearance of drafts;
• protect wood from damage.

An important factor is the choice of insulating material. The market provides a fairly wide selection of raw materials for caulking. These are moss, tow, euroline, jute, hemp, flaxjut and other analogues.

The main thing is that the selected material meets the following criteria:

• low thermal conductivity;
• breathability and hygroscopicity;
• durability;
• resistance to temperature fluctuations;
• high antiseptic properties;
• environmental friendliness.

Moss is the most inexpensive material that you can prepare yourself. It does not start a fungus, it does not rot, it is resistant to temperature changes, an absolutely environmentally friendly natural material with a long service life. Moss should be harvested in late autumn. In addition to drying, it requires pretreatment from soil, debris and insects. It must not be overdried, otherwise it becomes brittle. Purchased moss is pre-soaked.

Oakum is most often made from flax, but is found from hemp or jute. Like moss, it is carried away by birds. Available in belts or bales. The main drawback is that tow accumulates moisture, which undermines the wood. To neutralize this disadvantage, manufacturers impregnate the tow with resins. If earlier these were mainly safe wood resins, now oil products are increasingly used. Therefore, tow is no longer a completely environmentally friendly material, but it has excellent antiseptic properties and low cost.

Linen felt, also known as Eurolene, consists of linen fibers, intended specifically for insulation. Soft, pliable material is often available in rolls. It is more expensive than tow, but of higher quality, and also more convenient to use.

Sometimes flax felt is confused with flax. In fact, unstitched linen is the lowest quality linen felt. Flax often has impurities or impurities, therefore it is considered a budget option, and Eurolene is the purest analogue produced. Linen is not recommended by builders for caulking, especially stitched with cotton threads, which rot and spoil the wood. This material is more often used in the furniture industry.

Linen itself is not durable. Its service life does not exceed 10-15 years, the material cakes, becomes thinner, and is subject to temperature extremes. And although flax does not rot, it gives off all the accumulated moisture to the wood.It is important to note that its gray color stands out prominently between the crowns.

Oakum has a high cost, therefore it is not so popular.

Jute is an overseas material produced in India, Egypt and China. It is hygroscopic, does not rot, and is not attractive to birds. Due to its characteristics and low cost, the most common material for caulking. Among the disadvantages: jute does not have durability, it has coarse fibers. Available in the form of ropes, tow and tapes. The latter are more convenient to use.

Flax is a new insulation made from a mixture of jute and linen fibers. This combination makes the insulation durable and elastic at the same time. It is important to note that the higher the percentage of flax in the composition, the higher the thermal conductivity.

For work, you will need a special tool - caulk, as well as a mallet or a wooden hammer. The sealant is inserted into the slot with a caulk, and hit with a hammer to compact the material.

There are three stages of caulking.

1. When building a building. Initially, the insulation is laid between the crowns, including for buildings made of profiled timber.
2. After 1-1.5 years of operation of the building. During this period, the house shrinks the most. For example, a building with a height of 3 m can sag by 10 cm.
3. In 5-6 years. By this time, the house practically does not shrink. If on the outside of the house the insulation was laid under the siding, then caulking from the outside is not required.

Caulking begins sequentially from the lower or upper crowns, and in no case from the middle of the blockhouse. Insulation should be laid around the entire perimeter of the house. This means that it is necessary to seal the gaps between the first and second crowns and only then proceed to the third crown. If only one wall is caulked at first, then the house may warp. For the same reason, it is necessary to caulk not only from the inside, but at the same time also from the outside of the building.

After shrinkage, both small gaps and gaps of up to 2 cm can form. Therefore, two methods are distinguished: "stretching" and "set". With the "stretching" method, start from the corner, lay the insulation in the gap and clog it with caulking. If tape material is used, it is first rolled without tension along the wall, but not cut off. The end of the tape is tucked into the slot, then the protruding insulation is rolled up with a roller and filled with caulking between the bars.

Moss and tow is laid with fibers across the gap. Then it is rolled up and hammered, leaving the end sticking out from the outside. The next strand of material is intertwined with the end and do the same. There should be no interruptions.

The "in-set" method is suitable for large gaps up to 2 cm in size. It is better to use tape insulation, since it must be twisted into a bundle, and then into loops. This is more difficult with fibrous materials. The resulting cord is hammered into the slot, filling the entire space. Then a regular layer of insulation is laid on top.

The walls should be caulked until the caulk goes into the cracks by less than 0.5 cm. You can check the quality of the seams with a knife or a narrow spatula. If the blade goes more than 1.5 cm easily, then the job is poorly done. After caulking, the house can rise up to 10 cm, which is normal.

How to seal the walls in a house from a bar, see the video.