Where do cables run in walls?

Finding power cables in the wall: With these tips it works

If you damage a power line while drilling, you risk a life-threatening electric shock in the worst case. To prevent this from happening, you should know where the cables are under the plaster.

If a wardrobe or shelf has to be hung up, the powerful drill comes into play. Before starting, however, the wall should be examined specifically for cables installed behind it. The reason: You can only avoid damage with high consequential costs or even life-threatening accidents if you know exactly where the cables are running.

Find power cables: installation plan helps

The easiest way to find power lines is to use the blueprint. As a tenant, you can ask the homeowner about it. Homeowners are best advised to contact the craft company that laid the cables. She knows their route or has already made a complete plan of the pipeline route during installation.

Construction plan for a house: The electrics are also planned here. (Source: blickwinkel / imago images)

But if there is no plan or the company in question is not known, there is nothing left to do but to take action yourself.

Find power lines in the wall

Many hidden power cables can already be guessed from the position of switches, sockets or junction boxes. In modern buildings, power lines are usually laid according to precise rules. Installed by a professional, they usually only run vertically and horizontally to the ceiling and floor. As a rule, a specialist company lays the cables about 30 centimeters below the ceiling or 30 centimeters above the floor.

Our tip
Do-it-yourselfers cannot rely on this. In old buildings in particular, cables often criss-cross behind the wall. But even in modern buildings you can never be sure whether the cable routing has not been changed afterwards.

Using line finder: These are advantages

However, you can only play it safe if you drive over the drilling site several times with a good cable locator. Such power line finders can work on two different principles:

  • There are cable indicators that detect an electrical voltage behind the wall. In order to trace the course of a cable, the fuse must be switched on so that current can flow at all. If the line finder hits, a generous safety distance should be maintained when drilling. The devices are not exactly exact and sometimes show lines slightly offset.

  • But there are also cable locators that do not react to voltage, but to metal. The so-called metal indicators can be used to identify not only electricity, but also gas and water pipes, provided they are made of metal. The devices are sensitive enough to also display metal lines that run in a plastic conduit. However, the water pipes in many modern buildings are already made entirely of plastic. Of course, metal indicators do not find such plastic pipes.

Power cable drilled: this can happen

If a pipe is pierced, in the worst case scenario, there is a risk of death. Because if a cable is still live when it is pierced, you could receive a fatal electric shock. In the best case scenario, only the fuse pops out, there is a short circuit and a little flying sparks. However, you should not simply switch the fuse on again, but notify a specialist electrical company immediately.

Drilling holes: There can be power cables under a tiled wall. (Source: Jochen Tack / imago images)

But even if the fuse was outside while drilling, a power cable that was drilled through or drilled through is not to be trifled with. In any case, the drill has damaged the insulation, making the cable a safety risk. A drilled cable cannot cope with the same loads as an undamaged cable. At full power there is a risk of an apartment fire. In any case, the damaged cable must be repaired as quickly as possible.

Water or gas pipe hit: that has to be done

If you hit a water pipe while drilling, you should immediately turn off the nearest shut-off valve or the main tap in order to limit the damage. The repair should definitely be carried out by a professional. If water damage occurs later as a result of improper repairs, you could otherwise be held liable.

If you hit a gas pipe, you should immediately open all the windows in your apartment wide. After that, all residents must be warned. You are not allowed to ring the doorbell at the front door. If the bell is operated electrically, there is a risk of explosion. Only when you have brought yourself and the rest of the residents to safety should you call the gas supplier so that they can turn off the gas.

Drilling perfect holes: this is how it works

When drilling, however, you don't just have to pay attention to existing power lines. It is often not easy, especially for less experienced craftsmen who rarely have a drill in hand: Here it is important to choose the right drill or to determine the exact drilling depth. Use these tips to drill perfect holes in any material.

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  • Subjects:
  • Remodeling and renovation,
  • DIY,
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  • do it Yourself,
  • Craftsman,
  • Electricity,
  • Home & garden,
  • Home and garden,
  • Home & garden,
  • Tools,
  • To build,
  • Drill,
  • Drilling machine,
  • Water damage,
  • Gas,
  • Rental fee,
  • Accidents