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... 2 m ... additional connecting cable
for forming meshes
≤ 20 x 20 m

≤ 20 m

≤ 20 m 15 m
Figure 5.5.2.3 Foundation earth electrode
terminal lug Recommendation: Several
e.g. according to class of terminal lugs e.g. in every
LPS III at intervals of 15 m technical equipment room

Figure 5.5.2.2 Mesh of a foundation earth electrode

fore be carried out or supervised by a certified lightning
protection specialist or electrician.
The question of how to install the foundation earth electrode
depends on the measure required to ensure that the founda-
tion earth electrode is embedded in concrete on all sides.
Installation in non-reinforced concrete
Spacers must be used in non-reinforced foundations such as
strip foundations of residential buildings (Figure 5.5.2.3).
Only by using these spacers at intervals of approximately 2 m it
is ensured that the foundation earth electrode is “raised” and Figure 5.5.2.4 Foundation earth electrode in use
embedded in concrete (at least 5 cm) on all sides to protect the
foundation earth electrode (St/tZn) against corrosion.

Installation in reinforced concrete
In case of closed reinforced foundations, the foundation earth
electrode is installed on the lowest reinforcement layer. When
installed properly, a foundation earth electrode made of round
or strip steel (galvanised) is covered by concrete by at least
5 cm on all sides and is thus corrosion-resistant. The hygro-
scopic characteristics of concrete typically ensure a sufficiently
low earth resistance.

When using steel mats, reinforcement cages or reinforcing bars
in foundations, the foundation earth electrode should be con-
nected to these natural iron components at intervals of 2 m by
means of clamping or welding to improve the function of the
foundation earth electrode. Figure 5.5.2.5 Fixed earthing terminal

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