If you ask friends who have cottages, if they have any means of protection against lightning in their houses, then most of them will certainly answer negatively. The reason for this, most likely, is the inherent in our people's belief in the mighty Russian "maybe".And none of them thinks about what terrible consequences can occur if this mighty heavenly spark, which we habitually calls lightning, gets into the house. At the cost of the consequences, these are completely incompatible with the cost of materials and work on the installation of lightning protection( lightning rod), pouring out, in fact, in minimum amounts.
The electrical essence of lightning
Lightning, being an electrical discharge similar to the one that occurs when punching in electrical wiring, obeys all the laws that exist in the field of electricity. This powerful atmospheric discharge occurs in the place where the least resistance. The resistance, however, is less, the shorter the distance between the cloud carrying the electric potential and the object located on the surface of the earth. That is why often, heavy trees, poles or houses suffer from lightning strikes.
At the same time, one should not forget about the natural love of electricity for metal, since it is metal that is the medium in which there are ideal conditions for the movement of electric current. If for this heavenly spark to give a choice between a wooden and a steel pillar, then in any case it will choose the latter.
Principle of lightning protection
The principle of operation, and the lightning protection system itself, are surprisingly simple. The task of this system is to meet the lightning flying up to the roof of the house, to force it to change the direction of movement and send this lightning to the ground. In accordance with this three-pronged task, lightning protection includes three components: a lightning collector, a current collector and a grounding conductor.
Lightning protection construction
To protect against lightning strikes at the highest point of the roof, it is necessary to install a round rod made of steel with a diameter of about 12 mm using wooden supports. As a rod, you can use a steel pipe, pre-brewed or closed with a metal stopper its end. This rod is a lightning gate, which is destined to take the first blow. Its length can range from 20 to 150 cm, and the cross-sectional area should never be less than 1 cm2.
Pulling the collector from the roof, it is attached to the wall of the house with the help of staples. Then it is immersed in the ground and carefully welded at a depth of about one and a half meters to a pre-grounded earthing switch, whose role can play a sheet of steel or a piece of metal pipe. If there is no possibility to make earthworks for laying the earthing switch, then it is possible to use a metal rod, having hammered it into the ground to a depth of at least two meters.
This is the lightning protection design in the general case. However, for different types of roofs, there are different features.
Features of lightning protection for various types of roofs
Metal roof .In this case, the classical installation option described above is acceptable. Particular attention when installing lightning protection in any case, it should be noted that the current collector must be fixed to the wall of the house that is opposite to the entrance, and the earthing switch must be buried as far as possible from the basement and other structures available on the site.
Slate, wooden and similar roof types .In this case, it is recommended to change the shape of the lightning detector. For its arrangement along the ridge of a roof it is necessary to pull a metal cable, having established it on two props. The remaining elements of the system remain unchanged.
Tiled roofs .In this case, it is also recommended to change the shape of the lightning detector only. It is made in the form of steel mesh, the step of cells in which should not exceed 6 × 6 m. The mesh should not be particularly frequent.
Thus, we see that the installation of lightning protection is by no means a complex and costly exercise. Her presence provides the necessary level of protection, preventing the huge losses that a homeowner may suffer in the event of a direct hit of lightning in his cottage.
