Pierce the wall - you have to pay attention


When laying cables or connecting outdoor installations indoors, it is often necessary to pierce walls completely. What you have to pay attention to, and what you should know absolutely, read in detail in this post.

Typical problems with piercing

High wall thickness

An already fundamental problem is the required length of the drill. The usual thickness of internal walls is between 5 and 7 cm, bearing walls and outer walls can often be 24 or even 36 cm thick. Depending on the wall structure, sometimes even higher thicknesses are possible (facade insulation on the outside wall).

Hardness of the masonry

Not only concrete is difficult to pierce, but rather reinforced concrete. Even brick walls can be quite hard - and their big disadvantage is that the material is also brittle, and thus must be drilled without impact.

Unknown masonry

Especially with plastered walls is often not always clear which masonry it is. In solid construction, many different building materials are used, which also have very different characteristics and hardnesses.

However, the first drilling tests usually show, based on the color of the drilling dust, which wall building material is involved:

  • red or reddish dust: brick wall
  • gray dust: concrete or reinforced concrete
  • white dust: sand-lime brick (KS), which is also used as external building material, but mainly for partitions.

Suitable equipment and drills

To drill through hard walls, the drill must be powerful enough. For concrete and reinforced concrete, you can use a hammer drill, with brick walls should be paid attention as possible to the performance of the drill.

suitable drills

For most stable wall construction materials (ie drywall partitions), carbide-tipped masonry drills are a good choice.

pipe Run

Before starting to drill, always check to see if there are any pipes at the desired drilling site. The accidental drilling of water or power lines can have very bad consequences. Use a pipe locator for this purpose.

For reinforced concrete, you must also pay attention to the reinforcement (prefabricated concrete parts usually have a very fibrous tightly laid reinforcement, in-situ concrete reinforcements are thicker and more stable and usually not to pierce). The piercing of a massive reinforcement should also always be avoided for reasons of statics.

Right drilling

Brick walls (as well as clinker facades) may only be drilled through without impact equipment! In any case, you should:

  • Mark the drill hole with a cross, so that you could always fix the drill correctly
  • Always drill downwards on brick walls
  • drill at very low speed on brick walls (250-300 revolutions) as otherwise the bricks may glaze
  • Always drill all other wall building materials without impact and switch on the impact device only if drilling progress is too low

Tips & Tricks

If a helper presses a board against the opposite side of the wall while drilling, the plaster will be less damaged by the piercing drill.


Video Board: Attention to Detail: Carmelo Anthony