Lightning protection of a pitched roof: types and device. Lightning protection of a metal roof: how to make a roof lightning protection system

A partial list of components from different manufacturers, most often used when installing a lightning protection system on objects with a seam roof.

Buildings with metal cladding are very common. Metal coatings include corrugated board, metal tiles, seam or flat roofing from rolled or sheet steel. Seam roofing - a metal covering in which the sheets are connected by folds. Seam technology is used for roofs with a slope of more than 10 °. Sometimes they are mounted on more gentle ones, but then they are connected with a double fold and additionally insulated with a sealant. One of the disadvantages of this roof is the ability to accumulate a static charge. This can cause lightning to hit the roof. To protect yourself from negative consequences, it is worth making the roof grounding. People who are not too aware of the rules and regulations for lightning protection on a metal roof believe that a metal roof in itself is lightning protection. Indeed, RD 34.21.122-87 states that a metal roof can be used as a lightning rod. But it should be remembered that, firstly, the metal must be thick enough - 4-5 mm, or there should not be combustible materials under it (and this, you see, is quite rare). And secondly, the lightning rod is not a self-sufficient element of the lightning protection system - down conductors and grounding are also required. Therefore, in order to protect the building, as well as the people and equipment located in it, it is necessary to correctly calculate and install a lightning protection system, otherwise a roof with such a coating will accumulate an electric charge, which, if it is not diverted to the ground, can cause sparks between the roof and metal structures or electrical equipment, and thus provoke a fire.

№	Review	Code	Type	Name of product	Unit rev.	Base price excluding discounts and excluding VAT
1		5021081	RD 8-FT	Galvanized steel wire	M	66,24
2		800008		Round conductor D=8 mm, St/tZn 50 kg/128 m	M	48,56
3		5317207	270 8-10FT	Seam wire clamp	PC	484,08
4		365050	*	Seam angle terminal with increased contact area 0.7-8mm St/tZn	PC	291,67
5		5311500	249 8-10ST	Universal wire connector	PC	138,31
6		390050	*	Terminal MV Rd=8-10 mm with hexagon head bolt St/tZn	PC	141,67

Attaching a metal roof to a lightning protection mesh

Many people think that a metal roof does not need lightning protection. But still, the supervisory authorities require the use of torso or pin lightning rods.

Lightning protection of a metal roof

Of course, this is not a delusion. The roof is used as a lightning receiver, non-metal elements must have a lightning rod.

Of course, this cannot be one hundred percent guaranteed. Of course, a metal roof is a lightning receiver, and it must have a reliable electrical contact over its entire surface.

In this case, the ground electrode must be welded to the down conductor and the lightning rod. But if it is impossible to perform welding work, then it should be connected with bolts.

Take note! The metal tile and sheets must have an electrical connection between them.

Not only metal-based roofing, but also, which in turn are lightning rods, must be reinforced to the rafters. Based on statistics, if lightning hits the roof directly, this action is followed by a fire. This happens due to the fact that when the metal flooring is heated to a high temperature, which is more than the ignition temperature of the rafters made of wood.

Of course, most often metal tiles are laid on a crate made of wood, or they are laid on roofing material.

If a metal roof is used, it is best to connect it to ground. This action is beneficial and economical, but still not safe. It often happens that lightning hits a certain area of the roof, forming a flash.

There are cases when lightning strikes the roof itself, which had a thickness of roofing materials less than one millimeter, melting formed in place, which later turned into a fire.

With the help of the information we have listed, we will draw a conclusion. If the metal sheets are securely connected, the electrical connection between them is maintained, while being attached to materials that are non-combustible, then the roof will be considered a lightning rod. In this case, the thickness of the sheets is not taken into account.

Take advice! An alternative way is to ground the roof by installing cable and rod metal receivers from metal.

Do-it-yourself lightning protection

Let's take a closer look at the lightning rod device:

It is best that each building has a lightning rod in order to protect the house from fires, thereby preserving household appliances. This system has two types of protection: external and internal. As for the internal one, it is designed to protect the power grid from overvoltage after a lightning strike. External contributes to protection against impacts.

The external protection system includes lightning rods, down conductors, devices that are designed to ground the roof. The use of a metal pin or cone is the use of a lightning rod.

The external protection system includes special discharge devices that are able to limit overvoltage.

Of course, the internal system is not subject to independent construction, it is possible only to use it in the mains finished devices. Internal lightning protection has the easiest and cheapest way: turn off everything electrical devices, if after ten seconds the lightning has a gap after the thunder.

Outdoor lightning protection it is made independently, without taking a lot of time.

In addition to the above devices, a welding machine, a clamp or staples will be needed in order to connect the down conductor. In this case, it is made of wire, which has a cross section in the form of a circle. This kind of down conductor contributes to the unification in the place of grounding with a lightning rod.

It is possible to make a ground electrode from metal, which has a cross section of at least one hundred and fifty square millimeters. A steel bar with a diameter of eighteen millimeters is well suited. These elements are connected by electric welding or the use of a metal clamp.

Important! It is necessary to make grounding at a distance of one and a half meters from the location of the house. If we consider the height of the location of the lightning rod, then it depends on the location of the protective corner, approximately its coordinates are equal to seventy degrees.

The highest point is made in the form of the top of an umbrella. To avoid damage to the lightning rod, it is necessary to use a lightning rod installation a little higher.

How to make grounding?

In order to perform grounding, it is necessary to use a metal object, it is best that it has a large area to the maximum, it is buried to the very depths. A thick pipe or metal corner is well suited for grounding.

It is necessary to dig in to a depth that exceeds soil freezing. It is best to use a reinforcing mesh that is dug into the soil. It is made from thicker wire.

During the drought period, the available current penetrates the soil very poorly. Because of this, it is recommended that in the place where grounding occurs, it is necessary to maintain layers of moist soil. For this we will need waste water from the roof, which will be connected to the ground. If this method does not work, then use periodic watering to ground.

In order for the electrical conductivity to be highest level it is recommended to drill a hole after a certain period of annual periods and place salt in it.

Lightning protection is a bare conductor, which in turn has protection against corrosion. Most often it is made of aluminum or wire.

A- general form;
b- fixing the "fork" on the pipe;
rod lightning rod;
cable lightning rod;
racks;
blind area;
ground electrode;
humidification zone;
down conductor

There is an opinion that a lightning rod can protect the cone from impact different kind lightning. It depends on the vertex of its own view, including the side surface.

Helpful advice ! The area of its protection depends on how high you raise the lightning rod. If you place the lightning rod at a height of ten meters, then the cone will also end from the lightning rod at a distance of ten meters. It is best to have a tall tree in the area near the house. In this case, the lightning rod can be installed on a pole, which must be secured with a clamp. Raising the lightning rod will be higher than the tree itself.

If there is no tree, then the lightning rod can be attached to the antenna if it does not have metal surface and not dyed. In this case, it will be an excellent lightning rod.

If, nevertheless, the antenna has a wooden coating, then it should be wrapped with wire. After that, you need to connect the wire to the ground outlet.

There are times when there is no tall tree near the house, there is no mast available. In such cases, with the help of a chimney, it is possible to fix a lightning rod on it. To install a lightning rod, a metal pin connected to the ground level is hooked to the pipe.

The only point to be considered in this case. The pin used will be able to create loads due to the wind, thereby possibly damaging chimney, if it is poorly attached.

In this case, lightning protection is performed in this way.

on the sites, masts are installed two meters in size;
then a tight wire is pulled, which has an insulation level.
then bring this wire to the grounding area.

This option creates a zone to protect the house itself.

How to calculate lightning protection?

Of course, the calculation of lightning protection has a complex and difficult calculation. To date, there are many calculators that can calculate all this.

In order to calculate passive protection, you need to know the type of protected building. Whether it is a type of rectangular building that has a certain height, and other measuring calculations. It is an extended object or a single structure.

Then you need to know how many thunderstorms exist per year. Lightning strikes per square kilometer will depend on this. There are special cards for this. If you get all the values, then you will easily calculate the lightning protection for your area.

Lightning is a fairly common and dangerous natural phenomenon. Hitting a person can kill him, and hitting an ungrounded house can deprive him of lighting, disable all household and digital appliances. Houses with a metal roof are especially prone to it and require the installation of a lightning rod. How to do this, read the article.

There is an opinion that in a closed room lightning is not dangerous for a person, it can only deprive electricity and lighting. It's not like that at all. A lightning strike can start a fire, so it is important to attract the lightning near the roof and force the discharge into the ground. In addition, GOST assumes that any roofs of private houses should be provided with lightning protection. At apartment buildings it is established during construction by the state or the building contractor.

If there is no lightning protection on the roof of the house, the roof itself will be the lightning receiver. Usually the basis for a metal roof is either ruberoid or wooden planks. If struck directly by lightning, this backing layer may melt or ignite. Yes, and the metal roof itself can heat up to the ignition temperature of wood, which will cause a fire. Therefore, according to GOST a private house without lightning protection is included in the fire hazardous category, which can lead to fines during inspection.

A short circuit is also dangerous, which can not only ruin an expensive home appliances and deprive of lighting, well, and cause a fire no longer lining the roof, but inside the building. For all these reasons, a lightning rod is required for every home with a metal roof.

Types of lightning protection

According to GOST and reviews, there are several effective types of lightning protection for metal roofs:

rod. These are one or more vertical rods that are placed on the roof of the house or close to the building itself;
cable. It consists of one or two horizontal cables with fastening on two supports, where it lays a down conductor connected to an individual ground electrode. For such lightning protection, supports are placed on the building or nearby;
reticulate. In this embodiment, the current collector is placed on the roof itself with fasteners over the entire area. From it, the current lead goes to the ground electrode.

Also, ground electrodes are in-depth, surface or combined. They are usually made of pipes or solid steel. Everyone can choose the option that is more suitable for the home. There are also non-standard lattice structures - "Faraday cages", but according to GOST they are installed on large multi-apartment buildings.

Video “Grounding and lightning protection”

Installation on a metal roof

Installation of lightning protection on a house with a metal roof takes place in several stages. For work, you will need a lightning rod, lightning rod, ground electrode, brackets and a welding machine. The down conductor is preferably made of iron wire round section. A strip of metal with a diameter of 2 cm or more acts as a ground electrode.

The down conductor must be connected to the lightning rod, and from the other end to the ground electrode. To connect all three elements, you can use staples, but it is advisable to use electric welding.

The lightning rod should resemble the top of an umbrella at its highest point, and its location depends on the angle of protection (usually 70 degrees). Grounding is done at a distance of about one and a half meters from the house. Usually grounding conductors are made of metal pipe or corner. You can make a reinforcing mesh from thick wire.

Note that during the dry months, soil moisture becomes low, so it is better to do grounding in a shaded area. It is also possible to conduct a roof drain for water to the ground electrode system for humidification.

Studies have shown that the rod lightning rod has a certain protective cone, depending on the height and side surface. That is, for a receiver with a height of, for example, 10 meters, this one ends 10 meters from the lightning rod.

Separately, it is worth talking about lightning protection for metal scaffolding, prefabricated structures outside the house. These scaffolds are used for any assembly and construction work. According to the requirements of SNIP, metal scaffolding must be grounded immediately after installation. Work on the scaffolding can only be started after the installation of lightning protection.

Lightning protection of scaffolding involves the use of natural ground electrodes and lightning rods - pipes with a diameter of 6 cm and a length of up to 4 m. For each lightning rod, the lower end must be flattened and welded to each rack of scaffolding. Observe the distance between the pipes, when fixing on the scaffolding, no more than 20 m. The racks and supports of the scaffolding themselves will act as down conductors, and any discharge through them will go to the ground electrode buried in the ground. Also, cable or rod receivers can be used for lightning protection of scaffolding.

How the lightning rod mechanism works

The purpose of lightning protection is to take on a lightning strike, transfer it through the down conductor to the ground electrode. The mechanism of action is quite simple and consists of three parts:

lightning rod. An iron element that rises several meters above the roof, or wire on supports. Or a full-fledged mesh over the entire roof, with mandatory receivers on the ledges, if any;
down conductor made of thick copper or steel wire. Must be welded or otherwise connected to the receiver;
ground loop. Thanks to him, the discharge will be transmitted to the ground, where it will die out, without harm to the building and people. The larger the grounding area, the better. It is recommended to perform it in the form of a grid of thick metal rods.

A down conductor and a grounding conductor are present in all types of lightning protection, the difference is only in the design of the lightning rod. Doing it with your own hands is quite simple. Now your home household appliances and lighting is not threatened by a lightning strike.

Lightning protection of a metal roof is carried out by using pin or torso lightning rods. Although the roof itself can function as a conductor, the receiver itself must be located on it. But in order for the roof to be used as a lightning receiver more fully, it is necessary that it has a reliable electrical contact over the entire surface. Thus, all down conductors must either be firmly welded or bolted to the grounding elements.

Please note that in the case of arranging grounding, it is necessary to carry out a normalized electrical connection between the roof sheets.

In addition, the metal roof must be firmly fixed to the rafters. In this case, the entire truss system, each wooden element, must be treated with refractory substances. This is necessary because a direct lightning strike on a metal roof can cause a spontaneous fire. The reason is that under the action of high temperature, the roof, and from it the truss system, become very hot. To reduce the impact of high temperatures on the rafters, a roofing material is spread under the metal roof. This is not too costly economically, but it allows you to secure your home to some extent.

It should be noted that when a lightning strike hits a metal roofing element, a burn or melting may occur. Thus, if the metal roof is very thin, less than 1 mm, deep melting can occur. As a result - ignition and roofing material and truss system. Therefore, when choosing a roofing material, it is necessary to pay attention to its thickness and melting characteristics.

Based on all of the above, the following conclusion can be drawn:

The connection of sheets of metal roofing must be very strong, it is necessary to conduct an electrical connection between them, fix them on non-combustible material. It is in this case metal tile will be a lightning rod for itself.

Please note that if it is not economically viable to carry out all the work on grounding the metal tile, you can install grounded rod or torso lightning receivers.

In order to protect the house from ignition, as well as to maintain the working condition of all electrical appliances, it is necessary to build a lightning rod. The lightning rod consists of two parts: internal and external protection of the house.

Internal protection of the house is necessary to maintain the integrity of the electrical networks under the influence of overvoltage from a lightning strike.

External protection is designed to ensure the safety of the entire house from fire.

What is external and internal protection?

As a rule, this is a lightning rod, a grounding device and a down conductor. Any cone or pin made of a durable metal alloy is used as a lightning receiver.

The internal system is to use discharge devices for electricity networks, designed to limit the voltage level.

internal system to protect the house from power surges, it is impossible to completely do it yourself. But having certain skills in handling electrical wires and electrical appliances, you can integrate ready-made devices into the network.

Note. If the house is not equipped with a lightning rod and internal protection, during thunder and lightning, it is necessary to turn off all the equipment in the house from the power supply. Wherein this way only relevant if lightning follows thunder for 10 seconds.

Outdoor lightning protection can be done by yourself. The process is fast and not too expensive. However, it is necessary to have skills in working with a welding machine.

Thus, you will need a down conductor, a lightning rod, a ground electrode, several clamps and brackets made of soft metal, and a welding machine.

First of all, it is necessary to connect the down conductor to the lightning rod. The lightning rod is made of thick iron wire, with a sufficiently large cross section.

A ground electrode is made from a strip of metal. Its cross section must be at least 150 sq. mm. For these purposes, you can use a steel rod. With a diameter of about 18mm.

All structural elements are connected by electric welding or metal clamps, which are attached to nuts and bolts.

The grounding system is made not far from the house, 1.5 meters. At what height the grounding will be located completely depends on the position in which the protection angle will be equal to 70 °.

How to make lightning protection at home more effective?

Please note that the highest point of lightning retraction must be made in the form of a cone. Also, for reliability, you can install several lightning rods with one grounding at once.

How to make grounding with your own hands

Grounding is made from a metal object quite overall dimensions having a large area. It should be buried to the maximum depth. So. As an object for grounding, you can use a piece of pipe, a metal rafter angle. Often use a reinforcing mesh made of strong and thick wire, or metal barrel, even a solid thick sheet or a piece of iron will do.

Please note that it is necessary to bury an object for grounding to a depth that exceeds the depth of soil freezing.

How to make grounding more durable?

To increase the conductivity of electricity, holes are drilled every few years, and salt or nitrate is placed in them.

How to make lightning protection with your own hands

Lightning protection of a metal roof is a bare conductor treated with corrosion protection. As a rule, it is made of thick aluminum or copper wire. You can also use galvanized steel.

Physicists have established that a lightning rod protects a certain space, with an area of \u200b\u200bthe cone. The dimensions of this cone depend on the length of the lightning rod and the shape of its top. Thus, depending on how high the wire will be raised. The area of the protected space depends. The height reading must be started from the highest point on the site intended for protection. If this is the ridge of the roof, then from the ridge of the roof, if it is a chimney, then, accordingly, from the chimney. If there is a pipe, but it does not pose a threat, since it is not metal, a lightning rod can be fixed on it to increase the height. It should also be fixed with a conductor and ground. However, keep in mind that the pin, if it is heavy, can create a substantial load. It is necessary that the pipe is firmly fixed.

So, lightning protection of a metal roof, with fastening to a pipe, is performed as follows:

masts are installed on the gables, their height should be about 2 meters.
a thick insulated wire should be drawn and pulled between them;
the wire is pulled to ground.

If there is a tall tree near the house, then the lightning rod can be fixed on a long pole. Which, in turn, with the help of clamps, attach to the tree. Also, a television or cell tower, located near the house, can become an excellent lightning rod. But in this case, it should not be painted.

In the event that the mast is built of wood, a thick wire or a strong bare wire is allowed along its length. And connect it to ground. It is also necessary to install a lightning rod at the top of the mast, and connect it to the wire - conductor.

How is the lightning protection height calculated?

In order to make a calculation of the so-called "passive" protection, you need to know what type of structure, what height, length and width of the building. What is the object: a linear-broaching or single structure.

It is also necessary to establish the approximate number of annual lightning coming per 1 square meter in a given region. Detailed data can be found at the Hydrometeorological Center. It is by these values, by the level of danger, that the height of lightning protection is determined.

So, let's describe what the lightning protection design should be like in the end.
As we have already said, the whole structure will consist of the following elements:

Lightning rod, grounding conductor and conductor, that is, a lightning rod.

The lightning rod should consist of thick galvanized wire, which is mounted on the highest part of the house, that is, on a ridge or pipe. The conductor, made of the same thick wire, must be connected to the lightning rod and go down to the ground electrode. Often, the conductor is attached to a drainpipe or to the wall of a house. Fastening is done with metal clamps.

Note that the lightning rod is attached to the wall of the house at a certain distance, on special racks. If the house is wooden, then the length of the racks should be at least 10 cm, if the wall is brick or made of other non-combustible material, then the length of the racks should be about 5 cm.

The ground electrode is located at a non-freezing depth. For each region, this indicator is individual. The distance from the house is at least 1.5 meters.

Features of lightning reception

For a more accurate installation of a lightning rod, it will not be superfluous to know the following nuances:

Objects located at high altitudes attract lightning discharges not only above the top, but also from the peripheral sides of the thundercloud.
The most effective lightning rods are made of cable items. The use of a grid does not provide great guarantees of protection.
Remember that television antennas cannot be lightning rods. And it does not matter on which mast they are mounted, metal or wood. But if they are located not far from the lightning rod itself, part of the electric shock can pass to them.
It is undesirable to mount the lightning rod to the antenna. Due to non-compliance with the equipotentiality, a short circuit under roofing material, in the wires of the antenna.
At the moment of approaching the electric charge of lightning to the ground, the electric field, both at the surface of the earth and at the top of the building-.
If the lightning conductor is the metal roof itself, it is necessary to make sure that the electrical continuity between its elements is ensured for a long time.
If several lightning rods are used at once, then they should be located at a fairly large distance from each other. If there are more than two of them, then they must create a network, or, as they say, a "Faraday cage".

In conclusion, it should be noted that all the rules for the manufacture and installation of lightning protection elements must be observed absolutely exactly.
Independent construction of a lightning protection system is not difficult. Observing the safety rules, as well as the installation conditions for all lightning protection elements, as a result, you will get a completely reliable building.

Lightning protection for roofs made of soft materials allows you to protect buildings, especially wooden ones, from the effects of a thunderstorm. The lightning rod can be installed in several ways. At self-assembly system, it is important to follow the recommendations given in the instruction RD 34.21.122-87.

Roof part of lightning protection

A lightning strike into a building leads to fire and damage to property, poses a direct threat to human life. Roof lightning protection systems consist of:

receiver
down conductor;
ground electrode.

The lightning strike receiver is the device that first contacts the current. Based on the characteristics of the building, it is possible to use natural sources of protection, however, in most cases, the installation of special structures is required.

Down conductor - a wire that connects the receiver to the ground electrode. Mounted on the wall of a building or downpipe. Neutralization of lightning occurs in the ground. Approximately 50% of the total discharge is taken up by grounding, the rest of the voltage is distributed between the cable sheaths and water supply pipes.

The appearance and size of the device depends on the height of the building, the type of roof and the individual wishes of the customer, including aesthetic ones. In some cases, it is possible to combine several protection systems (active and passive).

The roof part usually consists of a lightning rod in various modifications. It can be a classic spire or a grid. For soft roofs, passive protection is usually used, however, each installation case is individual. When installing a lightning rod, all the recommendations set out in the installation instructions must be followed. Otherwise, the system will be unreliable and will not cope with its task.

Active lightning protection on a soft roof

This type of device is a mast that is installed on the roof. The receiving head with the ion source actively attracts the high-voltage discharge. This design allows you to catch lightning without leaving it a chance.

A significant advantage of this system is that the soft roof structure of the building is not damaged, while the level of protection is an order of magnitude higher than that of others. Installation of active protection is convenient, since a minimum number of movements on the roof is required. When working, the following points are taken into account:

The number of lightning protection masts depends on the area of the roof, the area to be protected from impact, and the type of roof (flat or pitched).
The receiver rod is installed at the highest point of the building, while rising at least 2 meters in height.

Important! When installing lightning protection for a soft roof, you should consider in advance the system for attaching the spires (to the chimney or water pipes).

Passive lightning protection on a soft roof

This type of lightning rod dissipates the electrical discharge due to its special structure. Passive protection is used quite often, especially in low-rise buildings. residential buildings and at production facilities. The lightning rod may look like this:

Metal pin. The structure is installed on the edge of the roof ridge. A wire with a cross section of 6 mm or more is lowered from it to the ground loop. The peculiarity of this protection lies in the fact that its part, located in the ground, is located 30 cm deeper than the level of soil freezing.
Cable. It is attached to the main lightning rod and runs through the entire roof. Grounding is arranged in any convenient way.
Lightning mesh. Installed directly on the roof soft cover or under it. This lightning protection flat roof is a mesh with a cross section of 6 mm. For gable roof two structures are being arranged: first for one half, then for the other. Grounding cannot be combined.

Note! When installing lightning protection under a roof, it is important that the insulation material is resistant to high temperatures. Recently, due to the risk of roof fire, this method of installation is not used.

The advantage of passive lightning protection is the ease of installation. In addition, skilled workers will be able to supply any of the listed installations without harming the flat roofing.

Down conductor

This element of lightning protection of a soft roof provides an electric discharge to the ground loop. The down conductor is made of thick wire (more than 6 mm), most often copper. This device, together with a lightning rod, is capable of extinguishing a voltage of 200 thousand amperes.

To reduce the likelihood of sparks, this element of lightning protection is positioned so that the discharge is evenly distributed along two parallel paths, the length of which should be minimal. All connections in the structure are made by welding.

The down conductors are located as follows:

both outside and inside (provided that the insulation material is non-combustible) of the facade;
0.1 mm or more from a flammable surface, if facing material buildings are fire hazardous;
away from door and window openings.

Important! When laying the down conductor, they try to create the shortest possible path to the ground loop, avoiding loops and twists.

If wire connections cannot be avoided, their number should be kept to a minimum. Down conductors are fastened as securely as possible to avoid breaking the conductors due to wind or other physical influences.

It is possible to use nearby facilities or design features building as a down conductor, subject to the following parameters:

metal carcass;
interconnected steel reinforcement;
the thickness of the elements is at least 0.5 mm;
half of the fasteners are made by welding or hard methods (bolts, tight twisting).

If it is planned to use reinforced concrete reinforcement or a building frame as down conductors, then it is possible not to lay horizontal belts.

Installation of the ground loop

Effective lightning protection is impossible without a design that absorbs and neutralizes the electric charge. Grounding must be located 5 meters from the entrance to the building and be inaccessible to children and pets. The material from which this part of the lightning protection is made can be any, but stainless metals are preferred: copper, aluminum and brass. The contour consists of several rods, the minimum value is 3-4 pieces per one- or two-story house.

Between themselves, the rods are combined with an electrical conductor. Thus, a closed system is created, outwardly resembling the letter "Sh".

On a note! The connection of the ground loop is done by welding or bolts. In no case is twisting applied. The structure is located at a distance of 1 meter from the walls of the house. To enhance the effect of conductivity, it is recommended to periodically wet the ground in the area of grounding with water.

Loop testing

Before commissioning the lightning protection system on soft roof conduct tests, during which they identify possible violations and inconsistencies in the design regulatory requirements. Verification includes several stages:

Comparison of the lightning protection of the building with the standards given in the document RD 34.21.122-87. Check the correctness of the choice of radius of action and design.
Inspection of the elements of the lightning protection system for the strength of the connection. Particular attention is paid to the quality of fastening and the absence of corrosion on the metal.
Welding points are checked by physical impact (hammer blows) for strength.
Measurement of resistance values on the ground loop. It should not exceed 10 ohms.

A three-pole test is used to measure the resistance of a lightning protection system. For its implementation, the ground electrode is inserted into the socket special device. The current meter is dug into the ground at a distance of about 40 m from lightning protection and connected to the measuring device. A metal potential probe is driven into the soil at a distance of 20 m from the lightning protection system and is also connected to the device. All elements line up, the switch on the measuring unit is set to RE 3p. After that, by pressing the Start button, you can read the readings.

Important! According to SNIP, every year it is necessary to check the grounding conductors for a reduction in the section thickness and, if it decreases by half, to carry out repair work.

Right installed system lightning protection on a soft roof will help save property and people's lives, so its installation must be carried out in compliance with all regulatory requirements.