All electrical work requires accuracy, increased attention, strict adherence to technical rules and established standards from the contractor. When planning and conducting the electrification of a wooden house, it is necessary to get advice from a qualified electrician, get acquainted with the regulatory documents, the basic requirements and the sequence of laying the electrical wire.
Requirements for electrical wiring in a wooden house
The installation of electrical wiring in wooden houses has some differences and features from the electrification of stone houses. When designing and laying cables, safety must be a priority. There are a number of basic rules that require strict implementation:
- Careful insulation of electric current conductors using non-combustible materials (NYM, VVGng, VVGng-LS).
- Aluminum conductors must be replaced with copper conductors with a cross section of at least 16 mm2. The cable must enter the house through a metal sleeve. The transition of the wire from one room to another is carried out through a rigid metal pipe.
- It is desirable to carry out electrification of a wooden house by an "open" method.
- It is necessary to carry out an accurate calculation of the cable thickness, leaving a margin of at least 30%.
- Particular attention should be paid to the quality of the materials used. It is necessary to choose a cable with non-flammable insulation.
- If it is necessary to install hidden electrical wiring, it is imperative to use a metal pipe. Laying cables in corrugated pipes is prohibited.
- Installation of an RCD, ground loop and lightning rod is required. In this case, not only electrical appliances are subject to grounding, but also metal pipes in which the cable is laid.
- The input node - the electrical panel should be isolated as much as possible from the wooden structures of the house. Sometimes you have to build a brick wall, and the floors are made of cement / concrete screed.
Wiring options in a wooden house
Do-it-yourself wiring in a wooden house, namely cabling, can be done in three ways:
Do-it-yourself wiring in a wooden house: diagrams
According to current regulations, when electrifying a private house without installing a transformer, the power consumption cannot exceed 15 kW. This indicator is calculated by summing the power of electrical appliances turned on at the same time. If the result obtained is less than 15 kW, then an introductory machine is set to 25A, otherwise a transformer is additionally required.
When developing a wiring diagram, the connection points are divided into different consumption groups. For example, lighting fixtures are powered from one machine, sockets require a separate device, and an additional one for street lighting.
It is advisable to equip personal machines and a separate power supply branch for powerful electrical equipment: an electric stove, a boiler or an electric boiler. Free-standing outbuildings also require separate automatic power supplies.
Important! For safety reasons, it is better to increase the number of power supply branches - this measure helps to reduce potentially dangerous connection sections.
Below is an approximate wiring diagram in a private wooden house with your own hands.
Some nuances in the development of the scheme:
- The introductory machine and the meter of the organization of energy supply require to be placed on the street for the convenience of controlling electricity consumption.
- For outdoor placement, the meter and circuit breaker must be in a sealed case that prevents moisture, dirt and dust from entering. Boxing protection class - not less than IP-55. The requirements for boxes installed inside a wooden structure are slightly lower - IP-44, the main condition is that the case is made of metal.
- For an emergency shutdown of electricity, it is necessary to place an RCD - the device will work in case of a short circuit in the network.
Do-it-yourself wiring in a wooden house: step by step instructions
Development of a power supply project
To develop an individual project in an electricity supply organization (RES), it is necessary to obtain technical conditions that will become the basis for further work.
The design of the power supply of a wooden house is carried out in the following sequence:
When organizing power supply and drafting a project, one should be guided not only by personal wishes, but also by certain requirements:
- Only vertical or horizontal wiring is allowed.
- All turns of the wire are performed strictly at right angles.
- Sockets, switches and junction boxes must be freely accessible.
- According to the rules, the installation of switches is carried out at a distance of 0.6-1.5 meters from the floor level, the cable is fed from above.
- The optimal placement of sockets is 0.5-0.8 m from the floor, the recommended number of sockets is 1 pc. for 6 sq.m. In rooms with a large number of household appliances, there will be more outlets.
- Wires must not be run closer than 10 cm from door / window openings. It is necessary to exclude the contact of wires with metal elements and nearby wires (the minimum allowable distance is 0.5 cm).
Selection of equipment and cables
To avoid complex calculations to determine the appropriate cable, you can use the reference book on electrical engineering. The cross section of the wire core directly depends on the expected loads.
The power consumption of equipment and electrical appliances is indicated in the technical data sheet or operating instructions. Based on these values, a wire with conductors of the desired cross section is selected. To determine the size of the input cable, it is necessary to sum up the power of the installed electrical appliances.
Advice. For a wooden house, you should choose a cable marked "NG" (do not support combustion) and "LS" (low smoke emission). Usually, wires with a cross section of 2.5 mm and 1.5 mm are used for internal wiring.
The introductory circuit breaker is selected with a rating sufficient so that at maximum load the power to the house does not turn off, but an open circuit occurs, preventing a short circuit.
For a single-phase supply, the circuit breaker is selected as follows:
When choosing switches and sockets, some parameters are taken into account:
- the amount of current for which the equipment is designed;
- installation option: external / hidden wiring;
- the number of keys - for switches, the number of places - for sockets.
- Household appliances with high power (electric stoves, washing machines, boilers, fireplaces, refrigerators, etc.) are subject to mandatory grounding. In such situations, it is advisable to use sockets with a terminal for connecting the ground wire.
- Triplets should be avoided. For the simultaneous connection of several electrical appliances, a group of sockets or dual models are installed.
- The choice of switches is determined by the lighting mode. To simultaneously turn on several light sources or one lamp, set the switch to one key, for different modes - two- and three-key.
Installation of the machine and input of power supply
According to the developed scheme, junction boxes are installed, the attachment points of switches, sockets and lighting devices are marked. In the designated place, the electrical panel housing is mounted and the following steps are performed:
- Installation in the meter shield housing.
- Installation of an introductory machine on a metal profile (din rail). An eyeliner to a two-pole automaton of phase and neutral.
- The terminals (output terminals) of the counter are connected to the input of the input machine.
- Planting a cable into the house and connecting it to the input terminals of the meter.
- A voltage relay, RCD, automata for various power groups (lighting, sockets) are installed on the DIN rail.
Cable entry into the house is carried out underground or by air. The second option will be cheaper, but such a supply is considered less reliable. With "air" input, self-supporting insulated wires are used. The main condition is the installation of a fireproof sleeve at the input site in the house.
With the underground method, a metal pipe is used for input, which protects the supply cable from various influences. Cable laying in this way must be agreed with the power distribution company.
Cable laying, installation of switches and sockets
The wire of the selected section according to the layout plan is laid in a closed or open way.
Do-it-yourself internal wiring technology in a wooden house:
Consider step by step how to conduct electrical wiring in a wooden house with your own hands using wall cable channels:
Important! The number of connections affects the ability of the system to carry loads - the more there are, the worse the load capacity.
RCD and grounding
The arrangement of the ground loop involves the following actions:
- Preparation of metal rods diameter 3 cm / length 3 m.
- Digging a trench 30 cm deep in a triangular shape, where the length of each side is 1 m. Install metal rods at the corners of the formed triangle.
- The connection of the reinforcement to each other with metal corners by welding.
- Weld an eyelet (loop) to one corner and fix a steel bar 1 cm thick on it.
- The rod is laid so that it is connected to the ground conductor in the electrical panel. The insulation of the grounding conductors of the cables is yellow-green.
After the meter in the shield, it is desirable to place an RCD. This device will protect a person from electric shock in case of leakage to the equipment case. RCD parameters are selected based on the value of the rated current in the network. Such a protective device is especially important for rooms with a high level of humidity (bathroom, sauna, swimming pool, etc.).
Do-it-yourself wiring in a wooden house: video
Common Newbie Mistakes
Electrification of a wooden house is a responsible event. According to statistics from fire organizations, most wooden structures ignite primarily due to a faulty electrical wiring. Some novice masters can ignore the advice of professionals and make a number of gross mistakes:
- Hiding wiring under wooden ceiling structures.
- Laying cables under the plinth.
- Use of corrugated PVC pipes for laying wire. Despite the practical qualities of the material and the convenience of its installation, PVC pipes are prohibited for use in the electrification of wooden buildings.
- The location of the insulated cable in the strobe without the use of a metal pipe.
- The use of plastic boxes for sockets and switches.
Private buildings made of timber and logs are distinguished by their external attractiveness, living comfort and environmental friendliness. But they are classified as buildings with increased fire hazard, due to the combustibility of wood. Therefore, wiring in a wooden house is carried out taking into account special requirements. They are set out in the Electrical Equipment section of the Building Regulations (SNiP) and the Electrical Installation Rules (PUE).
- A competent scrupulous calculation of the cable cross-section is required. Non-combustible material is used for their insulation.
- It is advisable to lay open wiring.
- Concealed wiring is not recommended for wooden structures. If you have to use it, you should work with cables in a metal pipe or in another sheath.
- In the switchboard, a protection device (RCD) and a circuit breaker are mounted and connected.
- The total capacity of the equipment that is planned to be installed in the dwelling is calculated.
- A power supply project is being prepared.
- Selection and purchase of switches, sockets, wires, technical devices.
- Power is being supplied to the building, a circuit breaker, an electric meter and a switchboard (PS) are connected.
- The cable is bred around the house.
- Mounted lighting fixtures, sockets, switches.
- A house plan is being drawn up. It marks the installation points of electrical appliances, lamps, switches, sockets, and other equipment.
- To connect the equipment, the appropriate type of cable is selected.
- On the wiring diagram, the places where the junction boxes will be placed are marked. One such device is usually used for two adjacent (adjacent) rooms in the house.
- The plan indicates the power of each electrical appliance (taking into account the starting force for installations with its own engine).
- Equipment that consumes a lot of energy (furnaces, heating boilers, water heaters) are combined into one group. A separate machine is used to connect them.
- Less powerful appliances (chandeliers, floor lamps, and so on) are collected in another group.
- Cable laying is carried out at the top or bottom of the wall with an indent of 0.2 m from the ceiling or floor.
- The switchboard is installed in the hallway of the house at a height of 150–170 cm so that children cannot reach it.
- Turns of internal wiring are made at an angle of 90 °.
- For reasons of aesthetics and ease of use, all switches are mounted at the same height (0.8–1.5 m). They are usually fixed from the side where the handle of the doors leading to the room is located.
- An electricity meter is mounted in the switchboard housing.
- A VA is placed on the DIN rail, to which the neutral and phase are connected.
- The input of the input machine is connected to the terminals of the metering device.
- Switches and voltage relays for RCDs and individual power groups are installed on the rail.
- All clamps of electrical equipment are connected by a wire to one core.
- Ceramic rollers that act as insulators. This method is optimal for dwellings with walls made of wooden logs.
- Plastic channels for cable fixed on vertical bases. These mounting fixtures are available in different colors, which makes it possible to choose them for any type of skin.
- PVC bracket. This technique is rarely used in homes because of its unattractiveness. It is more suitable for wiring in technical, utility and utility rooms.
- Corrugated pipes filled with cables up to a maximum of 40%.
- Special skirting boards equipped with a gutter. In the latter there are special fixators for the wire.
- The marking (according to the existing project) of the network laying line is being carried out.
- Remove the cover from the cable channel.
- Attach the box to the ceiling surface or wall. For this, self-tapping screws are used. Their installation is carried out in increments of 50 cm. At the turns of the route, additional hardware is screwed in.
- Junction boxes are mounted in the designated places.
- The wiring is placed in the cable channels, the latter are covered with a lid, and the fasteners are snapped into place.
- They make strobes in the walls.
- Distribution boxes are installed (so that access to them after facing the vertical bases is free).
- Install pipes. If necessary, they are pre-cut. The ends of the products are cleaned, all burrs are removed from them.
- Pipes are fastened with clamps.
- twist.
- Self-clamping Wago-terminals.
- Special caps.
- wires are stripped and twisted;
- cover the junction with the described product.
- Three reinforcing bars with a section of 3 and a length of 300 cm are cut.
- A triangular ditch 0.3 m deep with sides 1 m is dug in the courtyard of the house.
- The rods are mounted into the ground at the corners of the trench, connected to each other by welding and steel billets.
- An eye (loop) is attached to one of the bars. It is made of steel 10 mm thick.
- Rated current. Its value is taken an order of magnitude higher than the characteristics of the auto switch installed in the circuit.
- leakage current. For residential premises with normal humidity, devices with a response threshold of 30 mA are purchased, for bathrooms, bathrooms and kitchens - 10 mA.
- inspect the wiring for correct installation;
- measure the zero-phase resistance of the ground loop and insulation;
- check the operation of the RCD and machines.
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Installation requirements and general work plan
If you strictly adhere to the provisions of the PUE and SNiP, it is really possible to equip a reliable and safe power supply system for a wooden house with your own hands. First you need to familiarize yourself with the key requirements of these rules and regulations:
Wiring is divided into external and internal. The first is laid on the street and is connected to the home network through underground wells and channels or through the air (canopy).
External cables are usually made of wires with aluminum conductors, and only copper products are allowed to be used inside the dwelling. Their connection is carried out in a special adapter called a sleeve. It goes from the electric meter on the outer wall of the building to the switchboard.
Wiring in a wooden house is laid in stages. Experienced electricians are advised to adhere to the following sequence of work:
Lastly, the RCD is connected and the grounding system is equipped. After that, do-it-yourself wiring is tested for operability and safety of operation.
The nuances of drawing up a project for the energy supply of a wooden house
Work should begin by obtaining technical specifications from the local branch of the electricity supplier. Then they begin to calculate the total power of household appliances, lighting and other appliances. This operation is easy to do with your own hands, using the table below.
After the calculations, an electrical wiring diagram is created. The procedure is simple:
The diagram shows the distances from the line along which the cable is laid to all window and door openings and the removal of electrical points from the ceiling and floor surfaces. This is done so that later, if it is necessary to carry out repairs in the house, the probability of damage to the wiring is minimal.
During the design process, several important recommendations should be followed. Electricians advise working according to the following standards:
Sockets are installed at any height (PUE and SNiP do not stipulate this point). But the places of their installation should be thought out as competently as possible, taking into account the layout of large household appliances and furniture. Then, after repair, you will not have to use extension cords to connect electrical equipment.
Selection of wires, sockets, switches - the table will help
The electrical network in a wooden house works without accidents and failures if the cross-section of cables is correctly determined, with the help of which lighting, special equipment and household appliances are connected. For many home craftsmen, this part of the work causes difficulties. The table for selecting the diameter of copper conductors for devices operating under certain loads allows you to cope with them.
| Section, mm | Voltage, V | |||
| 380 | 220 | |||
| power, kWt | Current, A | power, kWt | Current, A | |
| 120 | 171,6 | 260 | 66,0 | 300 |
| 95 | 145,2 | 220 | 57,2 | 260 |
| 70 | 118,8 | 180 | 47,3 | 215 |
| 50 | 95,7 | 145 | 38,5 | 175 |
| 35 | 75,9 | 115 | 29,7 | 135 |
| 25 | 59,4 | 90 | 25,3 | 115 |
| 16 | 49,5 | 75 | 18,7 | 85 |
| 10 | 33,0 | 50 | 15,4 | 70 |
| 6 | 26,4 | 40 | 10,1 | 46 |
| 4 | 19,8 | 30 | 8,3 | 38 |
| 2,5 | 16,5 | 25 | 5,9 | 27 |
| 1,5 | 10,5 | 16 | 4,1 | 19 |
All electrical appliances have a technical passport or instructions for use. They indicate the loads that they consume. Based on this information, it is not difficult to select the required cables.
The safest wiring in a wooden house is obtained using NYM copper products. They are easy to install and process, have good strength, are equipped with additional insulation. Their only drawback is their high cost.
More affordable is the cable marked VVGng. Its insulation is carried out using PVC (polyvinyl chloride) plastic compound, which does not support combustion.
Switches and sockets are selected according to the type of wiring (open or hidden), the magnitude of the (calculated) current, the possibility of their connection on a single-frame block. Cables with three cores and mandatory grounding are connected to these network elements. The latter provides almost one hundred percent safety of operation of household appliances.
Introductory wire and machine - how to choose the right one?
To determine the cross section of the cable leading to the house, you need to calculate the total power (total rated load) of all available electrical devices and equipment. This is especially important if the wiring in a wooden house is being updated. That is, a complete replacement of auto switches and internal wiring is carried out.
If it is necessary to install a new lead-in cable on a log house or a residential building made of logs, contact the power supply organization. Its replacement is carried out before the installation and sealing of the electricity meter.
If the building network is designed for 380 V, a single-pole automatic machine is installed at the input. With a single-phase power supply (220 V), devices with 1 or two poles are used.
Experts advise choosing an automatic machine with a rating that, at maximum loads, does not turn off the current supply to the dwelling, but breaks the electrical circuit. Thus, it eliminates the risk of a short circuit.
It is easy to decide on the type, characteristics and rating of the introductory machine (VA) on your own. First, the power of all electrical equipment in the house is taken. According to the formula P / U * 0.8, the maximum current indicator is calculated. Its value is multiplied by a special coefficient of 1.1 and the value is obtained at which the switch at the input operates (in most cases, a 25 A fuse is used).
A suitable type of VA is selected according to the short circuit current (SCC). The formula used is: I = 3260 * S (wire cross section in millimeters) / L (cable length in meters).
The characteristic of the circuit breaker is determined by dividing the TKZ by the value of the rated current. For individual housing construction, it is recommended to use category C devices. They have shown themselves well when working in electrical networks with a mixed load.
VA is mounted after the counter. These two devices are mounted in an electrical panel on a DIN rail along with RCDs and automata for individual groups of equipment, after which they begin to lay cables around the dwelling.
Hidden and open wiring - features
Outside, the cable, as noted earlier, is mounted in metal pipes that are buried in the ground or in the air. The first method is more expensive, but really reliable.
Before the internal wiring in the house, the installation points of the switchboard and boxes, switches, sockets, and lighting fixtures are planned. RSH is fixed at the selected location. Then the following actions are performed:
Proceed directly to the wiring - hidden or open. The first is equipped in cases where the wall decoration in the dwelling is planned to be made as attractive and aesthetic as possible. It is ideal for newly built or overhauled log houses.
Hidden wiring involves placing cables in special non-combustible plastic or metal (aluminum, steel, copper) boxes. The latter are laid between the lining of the vertical surface and its base.
Open-type electrical wiring is installed in long-used houses and when creating retro interiors in new buildings. It is done with:
Important! It is desirable to equip the passages through the walls from one room to another with fire-resistant metal sleeves. And already through them to stretch the cables. In this case, the likelihood of a fire due to faulty wiring is significantly reduced.
Popular Indoor Cable Routing Methods
Open wiring is usually carried out using cable channels. Step-by-step instructions for performing such an operation are given below:
Important! At the mounting points of switches and sockets, a small amount of cable should be left. It is required to connect the specified elements.
The wires in the distribution boxes are connected to each other and to the terminals of sockets, circuit breakers, switches. This part of the installation work is described in detail in the next section.
With hidden wiring, the cable is often "hidden" in metal pipes. The algorithm of work is simple:
The wiring is pulled through fixed metal channels. In junction boxes, the conductors are twisted and insulated.
Briefly about the methods of connecting wires and the intricacies of the procedure
The operation is done by hand in one of three ways. A single internal wiring is created:
The first technique is inexpensive and available in implementation. The insulator (4–5 cm) is removed from the ends of the cables. The wires are twisted together, soldered and wrapped with a protective adhesive tape.
Wago technology involves removing 1 cm of insulation from the ends of the wires and connecting them using self-clamping terminals. The latter are selected according to the sections of the cables used.
The third method requires the purchase of special caps, inside which a conical spring is installed. How to use them:
The spring, when screwing on the cap, firmly clamps the electrical cable. And the plastic shell acts as an insulator.
Nuance. The load capacity of the internal route being laid depends on the number of wire connections. The more of them, the less reliable the wiring is in operation.
The final stages of work - little things remain
PUE require that all household electrical equipment with a metal case (refrigerators and freezers, washing machines, boilers, stoves) be grounded. This operation is easy to perform on your own:
The eye is connected in the electrical panel to the ground wire. It has a yellow-green insulating layer.
The residual current device is placed in the shield after the meter. It eliminates the risk of electric shock to a person during a breakdown of the latter on the housing of household appliances. RCD is selected according to two indicators:
After installation of all elements, the wiring is checked for safety of use and operability by specialists of certified electrical centers and laboratories. They conduct comprehensive tests:
The test results are recorded in the protocol. It must be presented to energy sales representatives who will come to seal the electricity meter.
A house made of wood is a beautiful, cozy building, but easily combustible, requiring increased attention to the power supply process. Making electrical wiring with your own hands is not an easy task, but doable. You just need to approach the issue responsibly, in compliance with the rules and regulations.
Electrical wiring in a wooden house must meet the main requirement - to be safe. More than half of fires in buildings of this type occur due to a short circuit in the electrical network due to mechanical damage to the insulation or increased load on the cable.
You can eliminate the risk of fire if you follow the basic requirements:
- Proper selection of materials.
- Reliable isolation.
- Possibility of automatic interruption of power supply.
- Regular network diagnostics.
Compliance with these requirements will reduce the likelihood of ignition of wooden structures and ensure the safety of property in both city and country houses.
Regulations
Regulations governing the arrangement of electrical power in wooden buildings are contained in "Rules for electrical installations" (PUE) and in the Code of Practice “Design and installation of electrical installations of residential and public buildings”.
They give criteria for choosing switchgears, conductors, automation, lighting, the terms used and their meaning are indicated.
Electrical wiring is still regulated by Building Codes and Rules ( SNiP).
SNiP 3.05-06-85 describe how to enter a power cable into a living space, and SNiP 31-02- requirements for the device of the power supply system in residential buildings.
Preparation of a power supply project
The first stage of electrification of the object is the preparation of the project. In a private house, drawing up a wiring diagram can be done on your own. To do this, you need a house plan with the placement of furniture, equipment, electrical appliances, the designation of sockets and switches. The place of installation of the switchboard and the passage of cable lines is noted.
The location of the junction boxes is indicated, the maximum power consumption of energy by all devices, the total number of machines and the rated load on the introductory machine are calculated.
Cable selection
After drawing up the electrical circuit, you need to decide which wire to make the wiring in a wooden house: aluminum or copper. The first one is cheaper, the second one is more reliable. Having settled on aluminum, you need to remember that its cross section must be larger than copper, and it is brittle when bent. A more suitable material is copper, the wires of which can withstand temperatures from -50 to +50 ° C.
Having decided in the house, you can proceed to the choice of its brand. For wooden structures, copper non-combustible wire VVG with solid cores and reduced smoke emission is more suitable. It has high anti-corrosion properties and does not deform under temperature changes.
When planning how to conduct wiring in a house, you need to remember the requirements of the Electrical Installation Code for the color of the insulation: the cable cores must be of different colors. This will simplify the process of installation, maintenance and repair.
The choice of devices and automation for the switchboard
The purpose of selecting automatic protection devices is the safety of the network and equipment in emergency situations. Each device has its own purpose. All devices are located in the switchboard.
Circuit breakers protect against voltage overload and short circuit.
(RCD) - from the occurrence of fire and electric shock.
Voltage relay - from load fluctuations that affect the operation of devices.
Combine the functions of a circuit breaker and an RCD and save space when installed in a switchboard.
The integrated use of these devices guarantees the reliable operation of the devices and the safety of people in the room.
Electrical wiring installation - step by step instructions
Installation of electrical wiring in a private house requires preliminary preparation and compliance with step-by-step instructions, consisting of the following steps:
- project development and determination of the total capacity of the equipment;
- choice of cable, automation devices and electrical appliances;
- power supply, connection of circuit breakers, electricity meter;
- installation of an electrical panel;
- internal cabling;
- installation of sockets, switches, lighting devices;
- system test.
Such a sequence will show how to properly wire the wiring in the house, and ensure the reliability of its operation. It is important to remember that each step must be carried out in compliance with safety rules: de-energize the room in which work is carried out, do not use bare wires, place all connections and branches in boxes, lay the cable either vertically or horizontally, preventing it from crossing.
Following the step-by-step instructions will allow you to perform the installation qualitatively.
Switchboard installation
The switchboard is designed to receive and distribute electricity in the room. With its installation, all electrical work begins. It does not matter whether the wiring is carried out in a country house, a city cottage or a rural log house.
The shield must be made of non-combustible material, placed in a dry place and locked with a key. Above it, rooms with high humidity cannot be located ( shower room, bathroom, bathroom), and within a radius of half a meter - heating equipment, water and gas supply systems.
An electric meter, an introductory machine, an RCD, grounding buses, voltage relays and machines for different power groups are mounted in the shield.
Grounding device
Any modern house is equipped with household appliances in a metal case, and the possible contact of metal with electricity requires grounding - protecting a person from electric shock through electrical appliances.
You can do it yourself.
A trench 30 cm deep is dug in the form of an equilateral triangle with a side of 1 m. Pins 3 m long and 3 cm in diameter are driven in at the corners, which are interconnected by a corner by welding.
A hole is cut in one of the corners, a ground wire is attached with a bolt and nut, which is connected to the busbar in the switchboard. Earthing conductors of cables in yellow-green insulation are attached to this bus.
Entering the power cable into the room
Electricity enters the building through a power cable that enters the switchboard. There are two ways to carry out its supply: air and underground.
In the first case, the cable is brought through the air from the electric pole to the house, where it is attached to porcelain fittings. This method is simple and cheap, but has a number of disadvantages: less durable, high probability of damage to the wire by wind, snow, branches.
The underground method is more reliable, but more laborious and expensive. A trench is dug, where an armored cable or in metal pipes is laid. A layer of sand 20 cm thick is poured on top, a signal tape is laid, and the trench is buried.
The main element of the wiring, because it bears the load from all electrical appliances in the house.
Cable laying and connection
Installation of electrical wiring in a private house is carried out along the routes indicated in the project scheme. Junction boxes are mounted on it, fixed, switches, lighting fixtures. In buildings made of wood, wires are used only with special markings, the insulation of which does not ignite even at high temperatures.
"Twisting", "temporaries" are not allowed. The number of turns and bends is best minimized. Where possible, run a whole wire from the machine to the end point.
When doing the installation of electrical wiring in a wooden house with your own hands, you must remember that the boxes cannot be closed with decorative panels or ceilings that make it difficult to access for maintenance.
Installation of switches and sockets
Overhead sockets and switches are selected based on the calculated current and the possibility of connecting under one frame. Before installation, turn off the power and make sure that there is no voltage in the cable.
The safest way to fix switches and sockets in a wooden structure is to mount them on metal substrates. This will protect against possible sparks when shorted or arcs when the plug is removed. For a wooden house, it is preferable to carbolite, rather than plastic, devices that have great heat resistance and can withstand strong heat.
Methods for open wiring
Open wiring in a wooden house is laid on the inside of the room. The main requirement is that the wire does not directly touch the walls, ceiling or floor and is protected: it is located in the middle of the channel, pipe or has several layers of insulation. Pipes and channels must be made of materials that do not support combustion.
Installation of wiring in a wooden house can be done in several ways:
- In a corrugated pipe made of PVC;
- In a metal hose;
- In PVC pipes or boxes;
- On staples;
- on ceramic insulators.
The most common options are the use of corrugated pipes and cable channels.
The use of ceramic insulators or "" is becoming popular, when air space remains between the twisted electrical wire and the wall. This option also decorates the home.
Open wiring in a wooden house can combine several options. On walls and ceilings that have a flat surface, you can use plastic boxes, and in other areas - corrugated pipes.
Hidden wiring in a wooden house
Internal wiring in a wooden house has its advantages and disadvantages. The advantage is the absence of corrugated pipes and cable channels that spoil the appearance of the room. There is no risk of mechanical damage to the cable. On the other hand, the complexity of installation, increased requirements for fire safety, additional financial costs.
Unlike external wiring, it is more difficult to conduct internal wiring in a wooden house. To do this, you need to know more requirements and nuances related to this type of power supply arrangement.
Hidden wiring should not have many turns, because. the cable must be laid in steel or copper pipes. The use of metal hoses and PVC corrugations is allowed only when they are protected with plaster or asbestos gasket.
If a special tool is not required for the installation of external wiring, then it is necessary for a hidden one. It is necessary to drill in horizontal and vertical directions, cutting out seats for insulating boxes. You will have to pull not only wires and cables, but also a large number of steel or copper pipes. The latter fit better, because they bend well, taking the desired shape.
You can conduct wiring in the house with your own hands in an open and closed way. This is done in places where the wire is connected to switches or sockets.
Mounting errors
Typical mistakes when laying the electrical network in the premises:
- bending or weakening of the supply cable;
- fastening the wire to a wooden structure, which is prohibited by the rules;
- installation of hidden wiring using corrugated pipes, metal hoses and plastic boxes;
- installation of the switchboard too close to the power cable entry point;
- the number of automata is calculated incorrectly: either more or less than necessary.
Wiring test
After installation, the wiring must be tested: conduct a visual inspection, measure the insulation resistance and the ground wire, check the operation of circuit breakers, RCDs or difavtomatov. The reliability of the electrical network must be maximum, because. electrical wiring requires increased attention and regular monitoring.
Wood in our country has long been the main building material. It was used by many generations of our predecessors.
It is very popular for the construction of modern environmentally friendly buildings from chopped logs, rounded or glued laminated timber, frame structures.
Electricity greatly facilitates the solution of everyday household tasks of the population. Not a single building can do without its use.
However, massively using electricity in a private wooden house, not all owners are well aware of the dangers that they create and even prevail in relation to the risks of residents of city buildings made of stone, brick, concrete slabs.
This is especially true for those who seek to combine the advantages of hidden wiring design ideas with wooden house designs.
Dangerous properties of wood in construction
From the point of view of electrical danger, a wooden house has two potential properties:
- high combustible characteristics of wood;
- change in dimensions, mobility of the overall structure due to gradual drying, loss of moisture.
Both of these factors must be taken into account during the construction and operation of the building.
Flammability
The fire hazard of wood is partially reduced by impregnation with special grades of solutions of special substances - flame retardants based on ammonium sulfate or nitrate salts, which melt when the temperature rises, covering the wood with its layer and additionally creating gas evolution that blocks combustion.
Such impregnation does not change the structure, the beautiful appearance of the texture of the fibers, their mechanical properties. But its purpose is only to limit for a short time the initial ignition of the surface layer from exposure to open fire.
In the event of a short circuit with failure and the formation of an electric arc or other method of arson, especially associated with the ignition of petroleum products, impregnation with flame retardants will not help. It was created in order to provide a small time delay for the start of a massive spread of fire throughout the structure of the house, to enable residents to jump out of a fire that has begun and save their lives.
This conclusion is easy to make if you watch a video by Vladimir Stroy about testing fire impregnation.
An experimental evaluation of the efficiency of this method by the specialists of the fire inspectorate fully confirmed its purpose.
This means that it is not at all worth counting on protecting wood from fire in this way, but other, more effective safety measures must be applied when installing electrical wiring.
Shrinkage in a wooden house
Natural sap flow is a necessary condition for the growth of any tree. Due to this, moisture always exists in its composition, which gradually decreases in building structures located in the air. In this case, there is a slight change in dimensions.
The walls of houses are gaining a consistent arrangement of logs. When each of them dries out even a little, then there is a general decrease in the height of the wall. This process is called shrinkage.
When erecting a building, builders take into account its manifestation, apply various technical solutions to prevent shrinkage of a three-meter wall up to 20 cm in height. To do this, perform special protection designs for window and door openings, as well as for fixing the roof.
They are performed in different ways.
When installing concealed electrical wiring, shrinkage should be taken into account and cables should be laid in such a way that the gradually changing geometry of the building does not harm their mechanical condition: eliminate breaks and crushing.
How to safely mount the cable in the hidden wiring of a house made of wood
Electrical safety rules provide that even during the factory production of a cable, defects can be made that will cause a short circuit and arcing. Various combinations of construction and operational factors, including erroneous human actions, can aggravate the likelihood of its occurrence.
Therefore, increased requirements are imposed on the design of the cable used in a wooden house. And it is unacceptable to carry out electrical wiring accidentally acquired. They can be the source of a fire.
Cable selection features
Conductor material
Let us immediately recall that modern rules in home wiring prohibit the use of aluminum thinner than 16 mm square for one core. There are many reasons for this. Among them are dominated by:
- increased fragility of the metal;
- plasticity of aluminum from the action of mechanical loads;
- high thermal conductivity;
- rapidly forming oxide film on the surface, which creates a high transition resistance to electrical contacts;
- formation of galvanic processes with copper alloys;
- quick heating when burning in air, like sparklers, while copper cools in a similar situation.
Therefore, all wiring inside a modern residential building is made only of copper.
Cable insulation material
The dielectric materials of any current-carrying conductor can have one of three fire-resistant properties:
- burn;
- do not support combustion:
- be fire resistant.
According to this principle, cable products are certified and marked in various ways. For example, according to the abbreviation of the VVG cable, it can be concluded that its insulating layer supports combustion. It cannot be used when installing electrical wiring in a wooden house.
If the abbreviation "ng" is added to the designation (for example, VVGng), which means the non-combustible properties of the insulation, then such a cable does not support combustion. It should be chosen for laying in a wooden building.
Fire-resistant cables are used for group laying at industrial facilities. They have a complex design and very high cost. Due to the significant price, they are not used in home construction.
Flame retardant cable fire properties
The dielectric material of the shell is specially selected for fire resistance. In the hidden electrical wiring of a wooden house, only cables are allowed for installation, the insulation of which does not spread the combustion process.
A short video by Vova Markov "VVGngLS - non-combustible cable" shows the various possibilities of insulating layers to counteract the influence of open fire.
The insulating layer in this design, when in contact with the flame, does not spread the combustion process, but under prolonged exposure to high temperature it can change - melt. And this leads to a short circuit and the further development of a fire.
Cables marked "ng", like all other electrical wiring elements, should not create direct contact with wood. They must be separated from it by a non-combustible layer - metal.
PUE requirements
The main document of electricians in its paragraph 7.1.38 clearly indicates three requirements for home wiring in a wooden house:
- create sealed metal spaces from pipes or ducts for hidden placement of all electrical wiring in them;
- prohibit the use of cables that support combustion;
- provide access to any damaged circuit elements for replacement.
Due to the first requirement, all electrical wiring is placed in housings that can localize the ignition process and prevent its development. This must be done because the cables run throughout the house, completely hidden from view. Any place can start a fire. It is almost impossible to find it quickly, even after discovering the beginning of smoke.
Experienced firefighters who have the appropriate equipment with them are not able to qualitatively apply it to the source of fire - it is necessary to find the place of ignition of the electrical wiring in the wall, and even get to it. During this time, the flame is completely transferred to the building structure, when it becomes problematic to extinguish it.
The situation can be aggravated by dry wood dust accumulated in all cracks. Under the influence of high temperature, it explodes and spreads fire throughout the building.
The principle of operation of the box for hidden electrical wiring
Electrical protection from circuit breakers and are designed to eliminate short circuit currents, overloads, leaks. However, they are technical devices, which means they can fail or not feel damage if they are not properly configured or selected.
Especially dangerous are current overloads and incorrectly selected machines and wires for them. The zone of operation of the thermal release provides for the supply of the electrical circuit with increased current, and the bad one overheats from it. This is where the source of the fire comes in.
In such a situation, only the absence of an influx of fresh air that feeds the fire, which does not allow a hermetically made case made of durable metal, can save. By blocking the access of oxygen, the fire is self-extinguishing.
Conduit designs for concealed electrical wiring
It is most affordable to lay cables in metal pipes and connect their ends with special containers with lids. To install switches, sockets, junction boxes, metal sockets and their analogues with cable entry sealing are used.
When assembling the component parts of the box, you can use:
- threaded connection;
- or welding.
In the first method, the electrical connection of all pipes and boxes with each other with additional wires through screw terminals is mandatory.
However, it is quite difficult to make them and properly mount them inside the structure of a wooden house. Therefore, many electricians simplify the work, and some customers support them, wanting to save on material and labor costs.
For cable installation, plastic or metal corrugated pipes are offered, which are easy to bend in the desired direction. At the same time, for some reason, the properties of the spread of open fire and the maintenance of combustion of the plastic corrugation are silent.
And with metal corrugations, not everything is safe. The fact is that the short-circuit current is capable of creating an electric arc of the order of 5000 degrees. Such a temperature is quite sufficient for burning through the thin-walled structure of the corrugation metal. And through the resulting cavity, the fire successfully breaks out to the wood.
Such recommendations should be treated critically, because the requirements of the EMP are written on the basis of a very large sad statistics of fires and incidents. They should not only be observed, but understood, and the consequences of violations should be presented.
Features of replacing elements of damaged electrical wiring
Inside the sealed box, it is necessary to provide for the installation of removable covers that provide access to the cable for its replacement in case of a malfunction.
This requirement of the PUE is taken into account at the creation stage. Otherwise, any damage to the power cable will create a lot of inconvenience for the owner of the house.
Wire shrinkage protection
"Sagging" of the wall with a metal pipe built into it, located along, can lead to mechanical failure of the cable.
This case must be provided with an exception:
- hard contact of building materials with the pipe of the sealed box;
- pipe deformation due to the inclusion of compensating structures that prevent compression forces from shrinkage.
Possibility of condensation
We are all well aware that the moisture contained in the air, when cooled, falls in drops, concentrating on the surrounding surfaces.
Hermetically sealed enclosure with cables located inside the walls. A warm temperature acts on it from the side of the room through sockets and switches, and from the opposite side - the streets through cold bridges. This process manifests itself differently in warm, temperate climates and frost zone conditions.
Residents of cold areas can watch moisture droplets appear on outlets throughout the long winter, reducing the overall. Practice has shown that it is very difficult to prevent the formation of condensate in hidden wiring.
To do this, it is required to perform its complete thermal insulation. Simple design solutions that allow condensation to be prevented in a limited metal space have not yet been proposed. It is problematic to effectively eliminate the temperature difference in pipes for hidden wiring of such an arrangement even in frosts up to 20 degrees.
Owners of wooden houses with properly executed hidden wiring in cold winters unsuccessfully struggle with the formation of moisture inside the box. Would you like to repeat their experiments? Do you know how to do it? Share your experience.
As additional material on the topic of the article, we recommend watching the video of the owner Sami with a mustache “Wiring in a wooden house”
Ask questions about hidden wiring in a wooden house, tell your friends about the material you read using the social network buttons.
In terms of electrical installation, wooden buildings are the most complex objects. We have prepared for you a set of rules for wiring in a wooden house, which discusses in detail the issues regarding the choice of materials and cable laying systems, as well as the installation of installation products.
1. Wiring in strict accordance with regulations
The organization of the electrical network in a wooden house is inferior in complexity only to buildings on a fixed polystyrene foam formwork. Laying on combustible bases is allowed only in an open way or with one hundred percent localization of the conductor inside the protective sheath.
This requirement is not so strict for frame internal partitions with non-combustible filler. In the most correct version, the passage of the cable through the racks of the frame is accompanied by the sleeve of the latter; in practice, most often the conductor is dressed completely in a corrugation or a metal hose, ensuring replacement.
Open laying is also a good solution. There are a number of fittings and installation techniques that make open wiring aesthetically acceptable and even add some color to the interior. In addition to plastic cable channels, it is possible to lay the PV-1 wire wound on ceramic insulators and use non-recessed housing installation fittings. In cases of hidden installation, non-combustible cable brands are used: VVGng or KGng.
Due to the complexity of the installation, cable routing along the walls should be kept to a minimum. But for this you need to thoroughly think over the scheme of laying cable lines.
2. Wiring diagram for walls and ceiling
In the most acceptable version of the electrical network around the house, each electrical point is connected in one straight line with a frame floor, ceiling or draft ceiling, covered with a suspended or tension coating. All the main wiring is carried out along the technological cavity, hidden from view, although more often the lines simply stretch one by one to the group shield. Naturally, the bulk of sockets and switches should be placed on internal walls, and on enclosing walls - only if necessary.
A reasonable solution would be to run the lighting wiring from the switches to the ceiling, and lead the wires for connecting sockets down to the floor. Due to their low load, the lighting network lines can be organized using junction boxes that are not accessible for maintenance. It is enough to bring the power line from the circuit breaker to such a box, and from it to lower the switching wire to the key and along the power line to each lighting group.
Lines of sockets and general-purpose groups can be combined into so-called garlands. It is important that no more than two wires are fixed on each terminal clamp of the sockets. Otherwise, each socket and group are connected in hidden junction boxes, and lines with a particularly high load from household appliances and heaters follow to the group shield without breaking.
It is recommended to cover the loops that gather on the wall at the group shield with a decorative casing. When laying cables in groups, it is also recommended to separate the base with a non-combustible substrate, for example, a piece of drywall.
3. Localization of conductors and branches
For some reason, exposed wiring may not be acceptable. In this case, the task becomes much more complicated, despite the fact that the part of the wiring laid along the walls is only 15-20% of the total length of the lines.
The possibility of hidden laying should be laid at the stage of pre-assembly of the log house. According to the internal power supply plan, technological channels for the cable are made in the walls as they are laid. For this, either electric chisels or core drills are used. The approximate width of the channel is 30-50 mm.
Outlets are drilled in the section of the frame system of the floor or ceilings. The installation of electrical fittings is possible by the recessed method, for this the channel is found with a probe and a hole is drilled with a core drill 60-80 mm in the beam array. Mounting boxes for sockets and switches should be made of steel, preferably with a fiberglass insert.
Pipe sections laid inside the walls must be localized from the environment. A smooth pipe is used for this: metal with a wall thickness of 2.5 mm or steel - from 1.2 mm. These values are indicative, a more accurate calculation requires taking into account the load and voltage on the line, as well as the type and number of conductors inside the sheath.
For branching power lines hidden in the cavities of frame structures, it is recommended to use metal boxes. For indoor installation, protection against wood dust with a degree of at least 3 is desirable, moisture protection is not taken into account. The input of the sheaths of cable lines should be flared, or equipped with a restrictive ring or nut that does not allow separation.
4. Safety devices
Wiring in a wooden house can be complicated by the peculiarities of the arrangement of group and switchboards. The difference is observed both in the method of mounting the cases, and in the selection of protective equipment.
Installation of the body of electrical panels must be carried out on a non-combustible base. Therefore, it is recommended to upholster the surface with tin under the central shields with ASU, and when installing group shields, use linings made of textolite or fiberglass.
It is convenient to connect group shields with ceiling and floor by cable channel, in which usually 3-4 lines are laid for each room. It is not recommended to place shields close to the ceiling or floor.
Circuit breakers are selected according to the permissible continuous current for the cable on the outgoing line, the choice is always made in the direction of a lower rating. Equipment that does not have internal short-circuit protection, as well as lines with a fixed maximum load (ovens, air conditioners) are connected through a circuit breaker with a rating for power consumption and a low delay in response to overload (characteristics B and A).
In wooden houses, it is customary to lay wiring in a three-wire circuit, where the protective conductor is not connected to zero. For this reason, the installation of differential protection against electric shock may be accompanied by false trips. But a fire-fighting type diffuser that monitors insulation leaks will be very useful.
5. Installation of installation products and fittings
At the final stage, the installation of fine electrics is carried out. This is most simply done using non-recessed fittings. It is easy enough to fasten it to a wooden wall with a pair of self-tapping screws, having previously inserted it into the case and connected the wires.
Much more time and effort is spent on the installation of hidden (recessed) fittings. For a tight fit of the frames, a flat surface is required, so the logs are pre-turned with a planer. Next, a hole is made connecting the surface with a hidden channel. It is used as a centering when drilling the installation niche with a hole cutter.
It is characteristic that installation boxes can be embedded in the same way as in stone walls - by landing on alabaster. Otherwise, the area must be localized and connected to the cable duct with a non-combustible rigid sleeve.
