Building with earth - Gernot MINKE (1)

Chapel of Reconciliation, Berlin,
Germany
The chapel stands at the border formerly
separating West from East Berlin, on the
site of the former neo-Gothic Church of
Reconciliation, which was demolished by
the then East German government. The
interior is of oval shape, and is delimited
by a rammed earth wall 7.2 m in height
and 0.6 m in thickness. The roof and outer
shell, formed by vertical wooden strips,
represents a second oval that is eccentrically
configured in relation to the first.
The rammed earth wall contains large fragments
of broken brick from the former
church, as well as gravel, which together
constitutes 55% of the material. The clay
content is only 4%. This coarse-grained mixture,
with a minimal moisture content of
8.1%, reduces material shrinkage to only
0.15 %. With a humidity level of 50 % and
a temperature of 20°C, the equilibrium
moisture content of the loam is 0.7 %.
The admixture of flax fibres and intensive
compaction with a tamping roller was
able to produce a compressive strength of
3.2 N/mm 2 (measured with 20 x 20 x 20 cm
cubes). The constantly changing radius of
curvature required the use of an intricate
special formwork.
Architects: Reitermann + Sassenroth, Berlin,
Germany
Completed: 2000
Area: 315 m 2
192
Built examples