Wooden houses and buildings belong to a special category   as building materials from wood are easily ignited. Take the issues of wiring in a wooden house very responsibly.

The best option would be to turn to professional electricians, but here too I have often encountered gross violations of the laying of electric cables over combustible grounds. Read this article to the end and you'll learn how to do it yourself with your own hands or require experts to perform electrical wiring in a wooden house, bathhouse, gazebo, etc.

Neglect common rules and norms is not necessary when laying electrical cables, because you put at risk not only your property, but most importantly yourself and the safety of your loved ones.

According to the norms and rules of electrical wiring in the walls, floor, ceiling, the materials of which support combustion - it is necessary to perform in metal pipes   or on the walls on a metal band. It is mandatory that all passes through the walls are made in metal pipes. All wiring (distribution) boxes and podrozetniki should be.

Simply put,   in the wooden house it is necessary to pull the second system of metal pipes, as for a water pipe, but only for laying electric wiring in them.

Besides, it is necessary to comply with other standards of electrical wiring, about which I already told in.

All pipes of metal connect with each other or with boxes by welding or threaded connection. It turns out that all the work of electrical wiring in wooden houses is very laborious and costly for materials.
  Much easier can be laid using a metal hose. In the end, and you will get it as shown in the picture.

  Many people ask, why there are such requirements. The thing is that at the moment of the breakdown of the cable, a short arc arises between the wires until the plugs break out or the circuit breaker breaks. At this point, and possibly the appearance of a spark and imagine that this will happen inside the walls, behind the ceiling or under the floor- there is a risk of fire.

In my practice there was a case when a wooden cottage was built and after the electric board was turned on, the roof caught fire because a nail in an electric cable was accidentally jammed. Metal protects not only from mechanical damages electroconducting through fault of people, but also from rodents.

I often meet when, wiring is done in a wooden house inside a PVC pipe, most often corrugated. Remember not to do this!

In extreme cases, do wiring in metal hose (but it will not protect from the nail) or metal-plastic pipes used for laying water.

The third point, the cable should only be copper and its cross section must correspond to the nominal   circuit breaker. For example, for a section of 1.5 square meters. mm. the machine is set to a maximum of 16 amperes, if you put it at 25 amperes, the electric cable will be heated when the level of the maximum permissible load for it is exceeded.

If the wiring is open outside the walls or ceilings everything is much easier. Many of her put in PVC boxes. At the same time, you do not accidentally damage the power cable, because you can see where it goes. And you can always check the cables if necessary. But unfortunately, according to the burning principles, the current rules do not allow this. As an output, it is a gasket in a metal hose in a PVC box, the color of which can also be matched to the color of the tree.

A wooden house, unlike a stone house, is an object of increased fire danger. That's why it's so important to strictly adhere to the rules that are set by firefighters. This primarily applies to various types of furnaces (cooking, heating) and electrical wiring. Most often in wooden houses an open wiring system is used, if a wire or cable is laid on the walls. If the gasket is made on the ceiling or floor (sometimes on walls), then hidden electrical wiring is used. So in this case it is necessary to use special boxes or metal sleeves of corrugated type (this is a kind of metal protection). What kind of metal hose for wiring in a wooden house is used today?

Varieties of metal corrugated hoses

At present, manufacturers offer three main types of metal hoses:

• РЗ-ЦХ;
• RZ-SL;
• metal hose in PVC insulation is non-combustible.

РЗ-ЦХ - this is the so-called unsealed corrugated hose. It is made of galvanized steel tape, in the sealing of joints of which cotton cloth is used.

RZ-SL is a corrugated hose that is made of tinplate. She before preliminary twisting in a sleeve (corrugation) process so-called electrolytic tinning, where the tin spraying is used. It is this tin layer that is an anti-corrosion protection, which extends the life of the corrugated sleeve. As insulation between the joints, polypropylene film is used. It withstands sufficiently severe moisture loads, so such a corrugated hose can be used for wiring in wet rooms.

Metal hose in PVC insulation is a sealed construction that can withstand a large number of different loads:

• mechanical;
• chemical;
• humidity;
• sun rays.

This type of metal sleeve can be used for both open and concealed wiring, and not only inside a wooden house, but also outside it. However, experts recommend that it be installed in tunnels, trenches or canals. Manufacturers also guarantee that metal hose in PVC insulation can be laid even in potentially explosive areas and areas.

In general, any hose in a PVC sheath is already protected from many unfavorable factors. At the same time, it is a great guarantee that when connecting a wire or cable laid in a corrugated hose made of PVC sheathing, it will be leakproof when the wiring enters the distribution shields, splitters and other devices or devices. It's all in the polyvinyl chloride shell itself, which, when clamped or mounted, creates a sealed joint.

There is another type of metal hose for electrical wiring, which is made of stainless steel. Expensive product, but with higher performance, especially for long-term operation.

What to choose?

To answer the question posed, it is necessary to determine the conditions under which the metal hose will be operated in a wooden house.

• If it is a wet room, then a sealed product is needed that does not allow wet air vapors to enter the sleeve where moisture or moisture will not contact the cable or wire itself.
• If the room is normal (residential or non-residential) with a normal moisture content, then an inexpensive leaky version of the RZ-CX can be used.
• If the operating conditions of the wiring are sufficiently rigid, then the optimum version of the metal hose with polymer insulation.

It must be added that the metal corrugated sleeve goes on sale in coils of length 50 or 30 meters. Cut it usually to the required size with a tool that is used for cutting metals: a hacksaw, a bulgarian, scissors and so on.

Couplings for connection

To connect the two pieces of electrical wiring enclosed in the corrugated hose, as well as when connecting them to various apparatuses or equipment, special fittings are required.

1. Threaded couplings with a special scratching nut. It provides additional grounding of the hose. Manufacturers offer direct couplings and angled, with external thread and internal.
2. Introductory couplings. They are used during the installation of wiring to shields, boxes or equipment.
3. Screw fastening element for special purposes. It is used when you need to connect the metal hose itself to a metal pipe, which is a kind of box for electrical wiring.
4. A straight coupling used to connect the two ends of the metal hose itself. It is a threaded element (internal two-sided thread), the thread pitch corresponds to the step of the turn of the sleeve.

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Many people prefer to live in wooden houses and carry out their construction to realize this desire. Of course, during the construction all necessary engineering systems are laid. One of the most important engineering systems is electrical.

I think you understand that the article will be devoted to the electrical system in a wooden house. Or rather, we'll look at how to install a hidden wiring in a wooden house. This process has many difficulties, but they can be overcome.

Before considering the features of the installation of hidden wiring should consider the features of a wooden house. Actually, they dictate all the requirements for laying electrical wires. And these requirements are quite tough.

Terms of use of the latent conducting

The main element, which consists of a wooden house, is a wooden beams. We all know that this material can easily catch fire. It's clear that people use houses that are wooden, so as not to cause a fire. That is, cautiously treated with fire.

Concealed wiring in metal hose

The cause of fire wood can be not only fire, but also a short circuit, which can be formed due to poor quality or incorrectly laid hidden wiring.

In fact, the closure is not terrible, because the tree does not conduct electricity. However, during a short circuit, an electric arc is formed in the wires. Actually, it is the main cause of fire.

This arc has a very high temperature. So, its level is a thousand times higher than the temperature of the flame in the gas stove. As you can see, there is no need to be a strong specialist to understand how warm the tree is in the area of ​​closure and how quickly it can catch fire.

It should be noted that this fact is taken into account in such a document as the PUE, which defines the rules for laying hidden wiring not only in a wooden house, but in any other houses.

To prevent the tree from burning due to a short circuit, this document requires the installation of any electrical cable in an element that will block and localize the flame created by the electric arc.

In other words, the flame should not go beyond such an element. This element is either a metal pipe, or a metal tray, or at least a one-centimeter layer of plaster.

metal cable tray

Using a copper pipe to lay the cable

Actually in them and you can lay a hidden wiring. All other options are strictly prohibited.

The tree has not only excellent ability to burn. It can increase under the influence of moisture, and also dry out. Consider the second option.

During the construction of a wooden house logs have a certain level of humidity.

After the construction of the house is over, these logs begin to dry out. As a result, the house shrinks, which in some places can lead to additional tension of the electrical cable.

Of course, it will not rupture, but the thickness of the insulation layer will become smaller, and this can lead to a short circuit. Here it is worth noting that if before the shrinkage of the wooden house to lay all the electric mains from metal pipes, then later some parts of the house will simply hang on them. Conclusion:   The hidden wiring in a wooden house must be installed after the drying.

The tree always absorbs moisture. So for the winter period in the room humidity increases and as a result, having absorbed moisture, the wooden elements swell. This fact can lead to an additional extension of the electric cable.

It is also known that the tree is a soft material, which easily lends itself to the teeth of rodents. This fact would not be terrible when the rodents damaged only the tree. In addition to wood, they like to gnaw the insulating layer of electric wires.

In most cases, they completely gnaw out the insulation (that is, up to the wire itself), which eventually causes a short circuit.

What can protect the wiring?

To ensure that these factors do not lead to the destruction of electrical wires and the occurrence of a short circuit, the buried wiring should have a reliable protection. As already noted, the methods of protecting it are a tube made of metal and a tray, as well as plaster.

If the use of the first two options is intuitive, then the use of the third one is slightly different from the standard method.

Its main feature is that the hidden wiring should be in the plaster, and not under it. That is, the installation of an electric cable on the wall and covering it with plaster is wrong.

First you need to apply at least a one-centimeter layer of plaster, then install the necessary wire, and then again apply plaster.

This method is used very rarely, since in general the internal wooden walls are used as a decorative element, that is, for interior decoration. The application of plaster creates both an additional load on the pocket, and the complexity of installing concealed wiring.

Now we know all the weaknesses of the log houses, and what dangers will be created by the incorrectly installed hidden wiring.

Advantages and disadvantages

Analyzing the above, you can determine some of the advantages that hidden wiring has. So, their list consists of the following items:

1. Proper concealment of the wiring (ie according to the PUE) makes it fireproof. The electrical cable is in such an element that not only does not allow the fire to pass, but also does not give access to fresh air to the place where a short circuit occurs.
2. Very low probability of damage to the wire. A pipe, tray or plaster protects the electrical wire from sunlight, heat and damp. This clearly affects the shelf life of the hidden wiring.
3. Saving of the conductor material.
4. The possibility of using the inside of wooden logs to create a spectacular interior.
5. Easy cable replacement, as it is freely placed in the middle of the tube.

If we talk about the shortcomings of hidden wiring in a wooden house, the main one is the complexity of the installation work and the large costs of purchasing these pipes or trays.
  To organize all the channels in which wiring will be located, you need to purchase special equipment.

Features of the scheme

The process of installing hidden wiring begins with the fact that a circuit is drawn up for each electrical wire. Of course, for this you need to determine the purpose of each room and the list of devices that will be used in a separate room.

Starting from this, they plan the places of outlets. Also determined and with the location of lighting devices and switches. Of course, sockets and lamps must be powered by various cables.

In addition, routes for various cables for an individual appliance (air conditioner, heating system element) or a group of electrical appliances are planned. It should be borne in mind that separate cables are needed for each room.

Useful advice: one of the main rules of circuit design is the design of such highways that have the shortest distance. Here it should be understood that to lay electrical cables you need to shrobit and drill wooden walls. The larger the slat and the holes, the more difficult it is to work and the more weaken the structure of the house itself.

It is best to lay pipes in the ceilings and then lower or lift the cables to switches and sockets. This option will significantly reduce the number of drilling and stamping operations.

It would be very good, if in the middle of the wooden house, there was an auxiliary room. In this room, you can place all the wiring (they can be mounted in an open way) and then, having made holes in the walls, conduct these cables to each adjacent room.

At the stage of drawing up the scheme, you need to determine the diameter and wall thickness of the pipes used. Normative documents determine that the thickness of the wall of the tube should depend on the cross-section of the cable that will pass through it.

True, there is some exception: if the cable cross section does not exceed 2.5 square meters. millimeters, the pipe can have any wall thickness.

Below is a plate that determines the dependence of the pipe wall thickness on the cable cross-section.

Determine the thickness of the pipe wall for the wire using a table

As for the diameter of the tube, it should be such that the wire or a group of wires fill only 40 percent of the inner space of the tube.

I think you realized that for the selection of pipes you will have to calculate the total power of the devices in a separate room and determine the current that each cable must withstand.

To do this, you need to divide the total power by 220 or 380 volts (depending on the presence of a 2- or 3-phase power supply). The current that the cable will pass through determines its maximum cross section. The section is determined using special tables.

When the schema is composed, you can proceed with the purchase of the necessary materials, tools and the beginning of the laying of the concealed wiring.

Required Materials

The list of materials should consist of:

• metal pipes (steel or copper);
• copper cable (should have a cross section of 1.5 for luminaires and 2.5 square millimeters for sockets);
• podrozetnikov (also should be metal);
• switches and sockets;
• terminal blocks;
• an introductory metal shield;
• boards of small width (they will serve as a plug for grooves);
• putty with the color of wood;
• joinery glue;
• wire.

Be sure to buy circuit breakers and RCDs. Their parameters should depend on the features of the concealed wiring diagram itself.

Required Tools

As for the tools, they should be presented:

• bulgarian or pipe cutter;
• drill, which should be equipped with drills for wood;
• benzo or electric saw;
• pipe bender;
• spatula;
• with a mounting knife;
• pliers;
• screwdrivers.

When all the necessary tools and materials are in a wooden house, you can proceed with the installation of hidden wiring. First, according to the scheme, it is necessary to install metal junction boxes.

Experts advise not to place junction boxes in walls or ceilings, since later there will be difficulties with access to them. Alternatively, they can be installed under the outlet itself. In this case, the hole is made deeper and the box is first placed. Next, install the top and the outlet.

Another option is to divide the outlets into groups and combine them with a loop.

The next step is to locate and secure the tubes or metal trays. If we talk about pipes, then the most optimal use of copper. The reason for this lies in the fact that they easily bend. However, they are expensive.

Good advice: copper pipes can be used in the most difficult areas. In other places, use steel pipes. In this case, you optimize your costs and simplify the installation procedure.

Using trays made of metal

Also, you can partially do without tubes. Instead, you can use trays that have special covers. They are made of galvanized steel. It is best to install them in the middle of the floors.

Metal hose for conducting concealed wiring

It should be borne in mind that the angles of rotation of these trays are sharp. Therefore, to protect the insulation of cables, they must be worn in corrugation. In this case, the cables can be completely worn in the corrugation or partially.

In the second case, the corrugation is used to protect the concealed wiring only in the zone of sharp corners of the trays, which are mounted by hand in a wooden house.

Such trays have different sizes and in some of them you can place a large number of electrical cables. At first glance, the installation of trays is easy, but the procedure for their installation is a troublesome job.

So, to lay them, you need to partially cut the joists and then strengthen them, you need to bypass each supporting structure, clean each sharp edge and earn ends.

In fact, to perform these operations, you need to have the skills of tin work. Each tray must be attached to another tray. For this use rivets or bolts with nuts.

Next, the trays insert wires and conduct earthing of metal trunk lines. The last procedure is due to the use of a ground wire. It is connected to each individual tray. This wire is screwed securely with a screw and a nut.

How to hide the pipes in the walls?

For the supply of individual cables to outlets and switches, it is better to use pipes. In this process, there will be greater complexity than they were when laying the hidden wiring in the ceiling. Here you need to cut special grooves in which the tube will be located.

Special pipe for cable in a wooden wall

The simplest way is to bring the hidden wiring to the switches. The fact is that the groove can be cut at the end of the wall, which then covers the door frame.

The switch itself should be at a distance of 15 cm from the box. Accordingly, at its location with the help of a crown, a hole is drilled. After that, you will need to drill a hole that will connect the groove and this groove.

Similarly, near the door you can place and sockets. However, we are used to the fact that the sockets must be located around the perimeter of the room. And here there are difficulties.

We will have to make a groove from the overlapping surface to the desired location of the outlet. It is not difficult. Complicated is the procedure for covering and masking this slot. Here you can not use the door frame, as in the previous case.

When the groove is propylene, a tube with a wire is inserted into it. The tube is grounded. To do this, take the steel clamps and attach using their ground wire. After the groove is closed with a special plug. This stub is made from a narrow board.

The board is greased with joinery glue and pounded into the groove. Then the board is pollinated and polished. After that, putty is put into each slot. Wait until it dries, and once again polish. The stub can be tinted and finished with a pattern that will duplicate the pattern of the logs.

Gofra and metal hose: is it possible?

It is worth noting that in some cases, for hiding a wiring in a wooden house they feed on metal hoses or corrugations. According to the PUE their use is not permissible. If we talk about corrugation, then it easily lends itself to the teeth of mice.

If we talk about metal hoses, then its weakness is its compaction. This seal is made of cotton thread. And she quickly flares up. Such a thread is equipped with metal hose RC-X. There are also metal hoses RC-A. It has an asbestos seal. However, it is released very rarely.

Other stages of installation

After the laying of the metal pipes and trays, install the junks. Using a nut, connect the mounting box to the tube. The connection can also take place by welding. The junction boxes are also fixed in the same way.

If copper pipes were used, then the ends of the pipes need to be expanded in the jars. In the end, there should be no ruptures between the tube and the podzheetnikami.

If there are no such gaps, a PE ground wire with a tube is connected in the switchboard. If there are gaps, then in these places it is necessary to connect the PE conductor and the tube.

According to the fire safety standards and the Rules of the Electrical Installation Device (PUE), there are only two ways to safely install a hidden electrical wiring in a wooden house:

1. installation in rigid metal pipes;
2. cable laying in protective corrugations, delimited from wooden structures with a layer of cement mortar or plaster.

Moreover, such clauses as "incombustible cable insulation", "metal hoses for hidden laying in a wooden house can be", "in Finland (Canada), etc. everything is built like this "by serious experts - electricians are not accepted.

To lay a cable or corrugation PVC in a continuous layer of cement mortar or gypsum mixture is quite a difficult task, and in practice this method of electrical installation is very rarely used.

(I could not even find pictures on the Internet :).

Why can not metal hose be used to mount electrical wiring in combustible structures? For two reasons:

1. Low localization ability of metal hose. Localization ability is the ability of a pipe (box) to withstand a short circuit of the wire inside without burning out the walls (see the table at the end of the article).

2. According to the rules, all metal elements of electrical wiring (steel pipes, metal hose, metal distribution boxes) normally not under voltage, must be grounded. In the case of a metal hose, this is difficult to do.

Special fittings for metal hose for connection to the box or interconnection are difficult to find on sale, and not all electricians know about it.

Use a metal hose without these important components or replace them with self-made bridges should not be.

We offer a simple and inexpensive solution for installing hidden electrical wiring in a wooden house: thin-walled metal pipes for electrical wiring.

Here you can buy metal pipes for electrical wiring   at affordable prices. The stock is available in stock in sufficient quantity to equip even the most serious projects for the electric supply of industrial facilities.

While we support the most popular sizes of thin-walled metal pipes for electrical wiring: ¾ and 1/2 ". But in the future we plan to expand the range.

It is obvious that the metal pipes themselves for the installation of electrical wiring without the corresponding components are practically useless.

We offer complete with pipes couplings for steel pipes ,   angles and staples for fixing steel pipes.