Anyone who has come across the replacement of electrical wiring in an apartment building knows that the most difficult thing is to replace it in the floor slabs, where it passes to supply voltage to ceiling lamps and chandeliers. This problem does not exist for apartments where there are suspended, stretch and other types of ceilings, in their design between the plate and the decorative plane there is a space in which you can lay wiring anywhere and in any way. But in the case when it is planned to paint the ceiling, paste over with wallpaper or foam tiles, this procedure can cause a lot of trouble. There are three types of floor slabs. The first two are structures with internal channels - voids, where the wires of the electrical wiring pass, the only difference is that they can go along or across the slab. If you are unlucky, you will have to face the third type, with a U-shaped one, in which there are no voids, and the wires pass under the floor of the upper neighbors, then there is only one way out - to make a suspended ceiling. In the first two cases, we start by expanding the hole through which the wire comes out to the chandelier. We do this with a perforator, with which we first drill the holes with a drill, and then we destroy the bridges with a nozzle - a chisel.
Now you need to determine the direction of the channel, since it may not be perpendicular to the walls. To do this, we drill control holes in the plate.
Having determined it, we find the place where the wire exits, it can be in the same room, or maybe in the next one, but always next to the branch box, which must be looked for under the old plaster and wallpaper.
In the place where wires from different rooms and different lines converge, you need to find the right one. To do this, we de-energize the apartment, disconnect all twists or couplings and find the desired one by dialing. Then, as at the beginning of work, we expand the hole in the plate and try to pull the wire from different ends one by one. With a certain amount of luck, he can immediately have a slack, but you shouldn't pull him out right there for joy. It is necessary to connect its end to the end of the new wire and carefully pull this twist through the channel.
If it was not possible to pull out immediately, you can increase the force with a tool, for example, with pliers, sharply pulling the wire from one end and the other, but in that case you can overdo it, the old aluminum wires are quite fragile and you can simply cut them off, then the further process becomes more complicated. Therefore, you should not rush, you need to firmly connect the end of the old wiring with a cut of any wire on both sides and alternately applying force without sudden jerks to try to pull it out. The channels in the slabs are quite large in diameter, but they can be clogged with debris or mortar that has got into them, so it is not always possible to pull out. If this happens, go to the next step, try to stretch the guiding probe. The material for it should be quite tough, but flexible. When it meets an obstacle, a soft one will bend, and a hard one will be difficult to give the right direction. The best option is a sheathed cable for cleaning sewers, it is quite flexible to change the direction of movement in the channel and does not hesitate when meeting an obstacle. We introduce the end of the cable into one of the two holes and, giving it the desired direction, move it forward.
When jammed, we do reciprocating movements with simultaneous twisting. If the channel is not tightly clogged with mortar, then everything will work out. Then we firmly attach a new wire to the cable, making the twist streamlined, without protruding corners and pull it through the channel.
If it so happens that the void is not passable, you can use the adjacent one, finding it with a trial drilling of the floor panel at a distance of 15 - 20 cm from the old hole. But this is acceptable when the slab is hollow and has several voids, but if it is monolithic with one special channel for wiring, then this option will not work and all that remains is to lead an external pipe, which is not welcomed by SNiP or to make a suspended ceiling.
do not "forget" about the new:
Federal Law of July 22, 2008 N 123-FZ
"Technical regulations on fire safety requirements"
Article 82. Fire safety requirements for electrical installations of buildings, structures and structures
1. Electrical installations of buildings, structures and structures must correspond to the class of the fire and explosion hazard zone in which they are installed, as well as the category and group of the combustible mixture.
2. Cables and wires of fire protection systems, means of ensuring the activities of fire protection units, fire detection systems, warning and evacuation control in case of fire, emergency lighting on evacuation routes, emergency ventilation and smoke protection, automatic fire extinguishing, internal fire water supply, elevators for transportation fire departments in buildings, structures and structures must remain operational in a fire during the time necessary for the complete evacuation of people to a safe area.
3. Cables from transformer substations of reserve power sources to input-distribution devices must be laid in separate fire-resistant ducts or have fire protection.
4. Lines of power supply of premises of buildings, structures and structures must have protective cut-off devices to prevent the occurrence of a fire in the event of a malfunction of electrical receivers. Installation rules and parameters of residual current devices must take into account the fire safety requirements established in accordance with this Federal Law.
5. Switchboards must have a design that excludes the spread of combustion outside the switchboard from the low-current compartment to the power compartment and vice versa.
6. Wiring of cables and wires from floor distribution boards to premises should be carried out in channels made of non-combustible building structures or molded fittings that meet fire safety requirements.
7. Horizontal and vertical channels for laying electrical cables and wires in buildings, structures and structures must be protected from the spread of fire. In places where cable channels, ducts, cables and wires pass through building structures with a standardized fire resistance limit, cable penetrations with a fire resistance limit not lower than the fire resistance limit of these structures must be provided.
8. Cables laid openly must be flame retardant.
9. Luminaires of emergency lighting on escape routes with autonomous power sources must be provided with devices to test their operability when simulating a disconnection of the main power source. The service life of an autonomous power source must provide emergency lighting along the escape routes during the estimated time of evacuation of people to a safe area.
10. Electrical equipment without means of fire and explosion protection is not allowed to be used in explosive, explosive and fire hazardous and fire hazardous premises of buildings, structures and structures that do not have additional protective measures aimed at eliminating the risk of an ignition source in a combustible environment.
11. Fire-proof electrical equipment is not allowed to be used in explosive and explosive-fire premises.
12. Explosion-proof electrical equipment is allowed to be used in fire-hazardous and non-flammable rooms, and in explosive rooms - provided that the category and group of the explosive mixture in the room correspond to the type of explosion protection of electrical equipment.
13. Rules for the use of electrical equipment, depending on the degree of its explosion and fire hazard in buildings, structures and structures for various purposes, as well as indicators of fire hazard of electrical equipment and methods for their determination are established by federal laws on technical regulations for these products and (or) regulatory documents on fire security.
Modern renovation is no longer just one chandelier hanging in the center of the room, we often highlight separate areas with our points of light or attach additional equipment to the ceiling, such as smoke or motion detectors.
Sometimes it happens that you need to solve a problem that can baffle an inexperienced craftsman, namely, laying wiring in the ceiling, without using suspended or suspended ceilings.
So we will try to fully disclose the topic of wiring in the ceiling, analyzing 5 ways to solve the problem.
Laying the wiring in a plastic box
Probably the easiest way to solve the wiring problem, which is related to the open method of wiring. There is no need to talk about the aesthetics of this method of laying, but it is fast in time.
The beauty: -
Simplicity: +
Laying wires on the floor of the upper floor
The wiring is laid in a protective corrugation along the floor of the upper floor in the gate or between the logs and through the through holes in the floor slab is lowered to the points of the lamps.
The method is convenient during a major overhaul of your house, but not quite suitable for apartments in a panel house.
Beauty: +
The work is dusty, but the result is worth it. If you have to embed a point light, or rather not so, if the thickness of the interfloor overlap allows you to embed point light, you can use special crowns for a perforator and cut out niches for them.
Beauty: +
Simplicity: -
Under-plastering in the ceiling
On the "dirty" ceiling, a flat wire PPV, GDP, PV1 is laid for more details on the types of wire in the article and plaster on beacons. It is important that the wire fits snugly to the ceiling, then less plaster will go away.
The method is used in monolithic floor slabs without voids.
Beauty: +
Simplicity: +
Laying wires in the voids of floor slabs
In the floor slab, there are void channels along them and pull wires. True, there are also disadvantages, such a channel must first be found, for this you can make a lot of holes in the reinforced concrete floor slab. In contrast to the method with slitting the interfloor overlap, the strength of the latter does not decrease.
After the channels-voids in the overlap have been found, a wire can be pulled along them using a wire.
In houses with concrete slabs of the PC type (with air ducts inside the pipe), it is possible to make hidden electrical wiring inside the slab.
There, wires are laid for chandeliers, lamps and even lines for sockets if necessary.
Now I will show how we changed the wire that goes to the chandelier from the junction box.
Do not forget that all work must be carried out with the voltage disconnected at the work site!
The most difficult thing was to find the entrance of the old electrical wiring into the channel of the stove, coming from the junction box.
Along the slab, a purely visual line was drawn, passing through the hole in the center of the slab for the chandelier - to the wall with the junction box.
At this point where the floor slab joins the wall where the proposed line ended and the plaster was hollowed out.
Having found the old wire in the wall, carefully grind the hole for its entry into the floor slab.
Carefully, this is so that not to interrupt this wire, it will still be useful to us.
Having gouged the hole, we release the wire from the remnants of the old plaster, mortar and, as far as possible, remove pebbles and other construction debris from the channel of the floor slab.
Slightly pulling on the old wire, we make sure that it freely walks along the channel in both directions.
Only after that we attach a new wire to it (naturally copper, with a cross section of at least 1.5 sq. Mm).
The main thing here is not to overdo it, the wire in the channel constantly clings to the walls and the remnants of the solution, and if you pull without measure, you just cut off the wire and you will have to start all over again and even look for the steel wire to lead through the channel.
That is, in principle, all the simple technology.
With new construction, construction is of course a little more difficult - you need to find a channel in the slab on both sides. Under the chandelier and the entrance of the wire to the stove.
Here you can find by sound the approximate location of the channel in the floor slab by tapping with a crowbar or hammer on the slab.
It is mainly found near the wall. You can drill a small hole with a punch. If the drill goes deeper than 5-7 cm, it means that the center of the channel was not hit, we drill another hole back a little until we find the channel.
Then we grind the plate in this place not very wide so that we can start a new wire. And we hammer along the slab along the channel, so that there is no sharp bend of the wire when entering the slab.
The smaller the bend, the easier the wire will be pulled.
After that, we take a rigid steel wire with a diameter of 2-3 mm and put it into the channel of the plate so that it hangs from both sides. Next, we attach the wire to be mounted to this steel and, pulling the wire, tighten the electrical wiring into place.
Then the place where the wire enters the slab (in the ceiling) is plastered.
Sometimes it happens that the channel in the floor slab is clogged with gravel or mortar and it is not possible to get the wire through the channel.
Then you have to make several vertical holes in the floor slab along the channel where the wire enters.
We push the wire as much as possible and measure how much it has entered the stove, then we look at this distance on the stove and make a hole in this place to remove stones or mortar residues.
If you only heard what words do not call in these cases the electricians of the builders who clogged the channels with garbage)))
in the same way, you can stretch not only the wire to the lamp, but also the main wires to the sockets, for example, from wall to wall.
There are situations where the wires are drawn in the channel of the slab near the wall (along it). It all depends on the situation.
Be the first to know about new site materials!
Before proceeding with the finishing of the ceiling surface, it is imperative to bring electrical wires to switches and sources of artificial lighting. Concealed ceiling wiring not only saves money on the purchase of cable, but is also a more reliable option from a security point of view.
Ceiling wiring - preparatory stage
Before you start installing electrical wiring on the ceiling, you need to solve the following tasks:
- decide on the optimal laying method;
- count the number of components, purchase them;
- think over the points where the junction boxes will be located;
- draw up a wiring diagram, while all wires should be located strictly at an angle of 90 °. On the drawing, outline the locations of the lamps and other lighting elements;
- using a special table, select the brand and section of the cable.
The wiring can be external or hidden.
The main types of outdoor wiring include:
- installation of the cable on non-combustible surfaces without the use of protective pipes (open);
- the cable is removed in special sleeves from the corrugation;
- use a metal corrugation;
- use steel or electrical pipes;
- laying is carried out in cable channels;
- wires are laid on special brackets and ceramic insulators.
Each type is chosen depending on the type of ceiling base and decorative finish.
Ceiling wiring: basic installation rules
If you do not have the knowledge and experience in the field of wiring, do not take risks, but entrust the work to specialists. If you are confident in your abilities and decided to cope with the task on your own, pay attention to the following recommendations, they will help you avoid mistakes when wiring:
- all electrical wiring must necessarily fit into protective corrugations. If this requirement is not observed, a fire may occur if a short circuit suddenly occurs;
- do not connect all appliances in the apartment to one residual current device. Even if the load does not exceed the design standards, it will still be inconvenient during further operation. In case of a short circuit in at least one consumer, all devices will turn off simultaneously;
- switches must be connected to the phase wire. If you ignore this requirement, even a trivial change of a light bulb can result in an electric shock;
- wires should not touch each other, as well as intersect with each other;
- before installation, it is necessary to make the correct choice of materials and wire cross-section. Choose not the section that is cheaper in cost, but the safest option;
- for bathrooms, kitchens and other rooms with high humidity, special electrical boxes should be used;
- Lay the wires in such a way that the electrical wiring can be repaired at any time.
Ceiling wiring - methods for different types of surfaces
When choosing materials for work, and when laying the wiring, be guided by the base surface of the ceiling, namely, the material that forms its basis:
- wood;
- metal;
- reinforced concrete.
Wooden ceiling base
To fix the cable to the wooden ceiling, you need to pull the wires through the steel pipes. Choose a pipe diameter such that the wiring will fit into it.
Junction boxes in this case must also be made of fire-resistant materials. The best option is metal boxes and pipes. On the inside, a layer of insulator is laid on them, which will prevent the wires from touching the walls of the box.
You need to act as follows:
- transfer the drawing to the surface from the paper drawing, carefully outline the cable installation lines;
- install junction boxes;
- cut the pipes to the desired length, fix them to the ceiling base;
- connect the individual parts of the pipes to each other by welding;
- using a broach, lay the wires through the pipes;
- take them out into the junction box, leave the ends about 20 cm each;
- connect all the conductors, wrap the joints with electrical tape and ground;
- now you can check the functionality.
Metal is an electrical conductor, therefore, for wiring to such an overlap, it is necessary to lay the wires inside special plastic pipes. In this case, the boxes must also be made of plastic. If it is impossible to use plastic products, then it is allowed to lay the cable in pipes or steel boxes.
The wiring is carried out in the same way with the cable laying along the wooden ceiling.
Reinforced concrete slabs, which form the basis of the base surface of the ceiling, are produced already with a ready-made gasket for boxes and pipes. In old houses, the cable is mounted on panels through the channels of the slab, which run along its surface and form voids in the slabs, and then the holes are plastered with a thick layer of putty. But in this case, the channels are often clogged with the remains of concrete from the chipping. If you have a similar situation, the wires must be mounted directly to the surface of the floor slab. For insulation, it is best to hide the cable in a corrugated protective tube made of non-combustible material.
Open laying of wires on a reinforced concrete ceiling is done according to one of the following options:
- cables are fixed to the ceiling with brackets;
- the wires are placed in a protective corrugated pipe, which is fixed to the ceiling with screws in plastic dowels;
- the cable is led into metal or steel pipes, and they are fastened to the ceiling with clamps or brackets;
- to protect the wiring, electrical pipes are used, which are mounted to the ceiling surface with clips.
During concealed installation, the wire is laid through the voids along the slabs. The transverse installation of the cable is prohibited, since it can violate the integrity of the floor.
The algorithm of actions will be as follows:
- retreat from the wall by 50-70 mm, put the first mark;
- make a recess 2 cm along the wall and 10 cm along the slab;
- the same actions are carried out at the location of the chandelier or lamp;
- a broach with a cable is brought into the channel, wires are removed from the other end of the pipe;
- after the cable is brought out, measure 40 cm, cut off the excess part;
- the cable cores are connected in a junction box, the joints are soldered, insulated;
- check the quality and integrity of the wiring.
False ceilings
Laying cables under different types of false ceilings has its own characteristics.
On a note! If you have chosen a closed method of installing electrical wiring under stretch ceilings, plasterboard structures or other suspended systems, all boxes must be fastened so that you can access them at any time.
The main feature of gypsum plasterboard ceilings is to restrict access to the base ceiling base. Therefore, before fixing the cable to the ceiling, it is necessary to provide service points for the entire system. Choose the installation method taking into account the type of base floor: metal, wood or reinforced concrete.
The plasterboard suspended ceiling reliably hides the wires, so the wiring can be carried out in an open way. The main thing is to take all the boxes outside the structure.
This ceiling belongs to the type of sheathing structures, therefore, the wiring will be carried out according to the type of cable laying for the gypsum board. At the same time, the junction boxes are also taken out of the ceiling system.
Since slatted ceilings are often used for bathroom furnishings, the following conditions must be met:
- if the base base is made of reinforced concrete, the cable must be laid in plastic or corrugated pipes;
- if the ceiling is made of wood, only metal or steel boxes and pipes are used.
Cassette ceilings have an advantage that distinguishes them favorably from other types of decorative ceilings: at any time, you can get unhindered access to the rough ceiling surface. Therefore, there is no need to move the boxes outside the structure, and the wiring can be completely hidden under the decorative trim.
If the wiring on the ceiling is done in an open way, then the pipes are fixed to the base with clamps or brackets.
In cases where the installation of wiring on the ceiling is carried out by a closed method, it is necessary:
- use metal or corrugated pipes for metal or reinforced concrete base foundations;
- steel pipes, if the floor is made of wood.
Electrical wiring under stretch ceilings is carried out by analogy with a plasterboard suspension system. The main requirement for the arrangement is to ensure a sufficient distance between the pipe with the cable and the tensioning web. Otherwise, a corrugated surface will remain visible under the coating.
Before the wiring under the stretch ceiling is carried out, you need to thoroughly think over the options for lighting the structure, and lead the wires to the intended locations of the devices.
Such ceilings are represented by special modules filled with polyurethane foam. They are equipped with plates that conduct electricity. In this case, up to five modules can be connected to one connector. The laying of wires is carried out, focusing on the material from which the main overlap is made, the boxes must be taken out of the ceiling.
The panels look spectacular in the dark when the rest of the lighting in the room is turned off.
Thus, when choosing a wiring option, you need to take into account the material from which the ceiling is made, the method of decorative finishing of the ceiling, and observe the entire technology of installation work from start to finish. Only then will the wiring be safe and durable.
Video - ceiling wiring