Installation zones: The invisible road network in our walls

Electrical installation zones form the backbone of every modern electrical installation. They are like a hidden road network that routes electricity and signals through our homes.

The basics of electrical installation zones

Electrical installation zones are defined areas in buildings in which electrical cables may be laid. These zones warrant that electrical installations are safe, efficient and easily accessible. They also help to trace the approximate route of cables and thus avoid accidental damage during subsequent work. This applies to horizontal and vertical mountings.

Horizontal installation zones

The horizontal installation zones form the main network for laying the cables:

Upper zone: 15 cm below the finished ceiling, 30 cm wide
Lower zone: 15 cm above the finished floor, 30 cm wide
Middle zone: In rooms with work surfaces, 100-130 cm above the floor, 30 cm wide

Vertical installation zones

Vertical zones connect the horizontal areas and enable the power supply of switches and sockets:

20 cm wide
Start 10 cm away from windows, doors, corners and structural edges

Cable routing on the ceiling

Installation zones under the ceiling form the central distribution network for laying cables in the upper room area:

In the room: at least 20 cm from the finished wall, 30 cm wide
In the doorway: at least 15 cm from the wall, 30 cm wide

Preferred heights for switches and sockets

Specifications for switches and sockets facilitate placement and contribute to uniformity in the electrical installation:

Centre zone: 105 cm above the finished floor (deviations possible for kitchen and utility rooms)
Lower zone: 30 cm above the finished floor

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For a quick overview of all important installation zones, you will find the most important rules and standards in clear graphics here.

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Special installation zones

Special regulations and safety requirements apply to electrical installations in living spaces, especially in areas with increased humidity or special usage requirements. Installations in kitchens, bathrooms and exteriors in particular must be carefully planned and executed to ensure safety and functionality.

Installation zones in the bathroom

Special regulations apply to electrical installations in bathrooms in order to guarantee safety in humid environments. The categorisation into four different protection zones determines where switches, sockets and light may be installed and which protection ratings are required. Particularly in zones 0, 1 and 2, strict regulations apply to minimise the risk of electrical accidents. For example, electrical installations in the immediate vicinity of showers and bathtubs must have a degree of protection of min. IPX4, while in zone 0 only specially approved devices with safety extra-low voltage (SELV) up to 12 V are permitted.

Zone 0

Zone 0 is inside the shower or bathtub. Electrical installations are generally prohibited here, with the exception of specially authorised devices such as underwater lighting

Zone 1

Zone 1 runs vertically above zone 0 up to a height of 2.25 metres. Only permanently mounted, splashproof devices such as instantaneous water heaters are permitted here.

Zone 2

Zone 2 runs 60 cm around zone 1. Lamps with protection class IPX4 (splashproof) may be installed here, but no switches or sockets.

Zone 3

Zone 3 is located at a distance of 2.40 m from zone 2. Standard switches and connections are permitted here, provided they have a residual current circuit breaker (max. 30 mA)

Installation zones in the kitchen

The kitchen is a central work area in the household where electrical installations need to be well thought out. Due to the combination of water, heat and electrical devices, special requirements apply to the placement of sockets, switches and connections. In addition to the horizontal installation zones at floor and switch height, there is also a centre installation zone in the kitchen. This is particularly important for sockets above the worktop so that kitchen appliances can be used comfortably. Minimum distances from the sink and cooker must be maintained.

Horizontal installation zones

Upper zone: from 130 cm to the ceiling
Middle zone: 100-130 cm above the finished floor edge
Lower zone: 20-30 cm above the finished floor edge

Vertical installation zones

Upper zone: From 130 cm to the ceiling
Middle zone: 100-130 cm above the finished floor edge
Lower zone: From the floor to 30 cm above the finished floor edge

Special heights for electrical connections

Minimum distance to water connections: 60 cm for sockets and switches
Switch height for light sources: 105 cm above FFB as standard Recommended number of sockets: 6-10, per kitchen equipment

Installation zones in exteriors

Installation zones are also essential in outdoor areas, to ensure that electrical cables are laid safely and efficiently. Horizontal zones along building facades are used, for example, for laying main cables, whilst vertical zones allow for connections to outdoor lighting, sockets, or other devices. As outdoor installations are exposed to the elements, all components must have a suitable protection rating, at least IP44, to be protected against moisture and foreign objects.

Horizontal installation zones outside

Upper zone: 20 to 40 cm below the interior ceiling
Lower zone: 20 to 40 cm above the floor

Vertical installation zones outside

On doors: 10 to 30 cm from the edge of the building shell
On windows: 10 to 30 cm from the edge of the shell
On wall edges: 50 to 70 cm next to shell edges

Switches and sockets with IP44 degree of protection

Thanks to a hinged lid, switches and sockets with degree of protection IP44 offer reliable protection against foreign objects such as wires or small tools. They are also resistant to splashing water from all directions. In interiors, they are ideal for areas with increased moisture, while in exteriors they are suitable for covered zones such as balconies, where they may be exposed to splashing water, but not permanent wetness.

Further contributions

This is how many sockets make sense

Electrical installation for exteriors

The versatile world of light switches

The right approach to renovating old buildings

The importance of electrical installation zones

Electrical installation zones play a decisive role in the safe and efficient design of electrical systems in buildings. These standardised areas for laying cables and placing switches and sockets offer numerous advantages.

Security

The defined zones reduce the risk of accidents and damage. If tradesmen know where the pipes are located, they can proceed with greater caution during renovations or conversions.

Cost savings

The standardised arrangement of the electrical installation zones prevents unnecessary drilling errors and damage, which reduces repair costs. The clear structure also makes maintenance easier, resulting in lower operating costs.

Efficiency

The standardised arrangement simplifies planning and installation. Electricians can work more efficiently as they know exactly where cables should be laid.

Flexibility

The zones allow flexible organisation of the electrical installation. They offer sufficient space for future extensions or changes.

Electrical installation in residential buildings

The DIN 18015standard regulates electrical installations in residential buildings. It specifies how equipment should be arranged and cables routed. Although DIN 18015 is not legally binding, it is often stipulated in building and work contracts and is considered a recognised rule of technology. DIN 18015 only applies to invisibly laid cables; it does not apply to visible surface-mounted installations.

Challenges, solutions and future prospects

The conversion of electrical installation zones in practice poses various challenges, requires innovative solutions and opens up interesting prospects for the future. In this section, we look at some of the most important aspects.

Old buildings

In older buildings, the installation zones may deviate from the current standards. Until 2007, for example, the centre zone was between 90 and 120 cm above the floor. This must be taken into account during renovations.

Complex room geometries

Not every room is a simple rectangle. With complex floor plans, planners have to get creative to optimise the use of installation zones while complying with standards.

Smart Home integration

As Smart Home technologies become more widespread, installation zones may need to be adapted to integrate new types of sensors and control devices.

Energy efficiency

Future standards could include installation zones for energy-efficient systems such as smart meters or home energy storage systems.

Conclusion

Electrical installation zones are an essential, yet often invisible, part of modern buildings. They form the foundation for safe, efficient and flexible electrical installations. For architects and electricians, understanding these zones is essential in order to create buildings that not only meet current requirements but are also equipped for future technological developments.

Paying attention to installation zones may seem like an additional constraint at first glance, but they actually provide a structured frame that makes work easier and improves the quality of the electrical installation. They are the invisible backbone that holds our modern, electrified living spaces together and ensures that electricity always flows to where it is needed - efficiently and future-proof.

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