Building with earth - Gernot MINKE (1)

6Working with earthen blocks
Illustration 6.1 shows different shapes and
sizes of green bricks produced industrially
by an extrusion process common in the
German market. Specific applications of
these different types of blocks in walls,
floors, vaults and domes are described in
chapter 14.
History
6.1
6.1 Industrially produced
green bricks,
Germany
6.2 Ancient core
of the city of Shibam,
Yemen
6.2
Blocks of earth produced manually by
throwing wet earth into a formwork are
called “adobes” or “mud bricks” or “sundried
earth blocks.” When moist earth is
compacted in a manual or powered press,
the compressed elements so formed are
called “soil blocks.” In their unbaked state,
bricks produced by an extruder in a brick
plant are called “green bricks.” These three
types of blocks are usually the same size as
baked bricks. Larger blocks, compacted in a
formwork by ramming, are called “rammed
earth blocks.”
Some countries have standardised measurements
for these blocks. The two sizes used
most commonly in Germany, for example,
are:
NF (normal format) = 71 x 115 x 240 mm
2DF (double thin format) = 113 x 115 x 240
mm.
Building with earthen blocks is widespread
in all hot-dry, subtropical and moderate
climates. Earth block buildings dating from
8000 to 6000 BC have been found in
Turkestan (Pumpelly, 1908), and ones from
ca. 4000 BC in Assyria. Visible even today
in Upper Egypt are monumental structures
about 3200 years old, such as the huge
earth block fortification wall of Medinet
Habu and the vaults of the storage rooms
in the temple area of Ramses II near
Gourna (1.1).
The technique of making vaults and domes
from earth blocks without supports during
construction (centring or shuttering) was
known to many cultures (see chapter 14,
p. 117). For centuries, Pueblo Indians in Taos,
New Mexico, built their houses using the
earth from the sites themselves, the water
from nearby streams, and straw from the
fields (6.3).
The historical core of the city of Shibam,
Yemen, covering about 20,000 m 2 and
accessible only through a single gateway,
was built entirely in adobe. Many houses
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Working with earthen blocks