The rammed earth technique is an ancient construction technique,
with roots extending deep into architectural history.
This technology dates back to ancient civilizations,
and bears witness to humanity’s ingenuity and ability to adapt.
Construction using rammed earth
Construction with rammed earth involves compressing a mixture of moist soil between solid forms until it becomes as solid as concrete.
Although this technology is ancient in its origins,
it carries within it the beauty of simplicity and the dream of sustainability.
It is simply the process of compacting or compressing ground materials into a solid, dense wall.
The result is a durable and aesthetically unique structure with cracks that bear witness to its construction layer by layer.
Components of rammed earth
Sand: It constitutes the bulk of the mixture and provides the necessary granules for compaction,
with particles coarse enough to interlock.
But it is not so large that it leaves voids or weakens the structure.
Gravel: Gravel enhances the structural integrity of the mixture,
and its percentage can vary depending on the design specifications and required strength.
Clay: Although not essential in the mixture, it acts as a binder,
and its cohesive nature ensures that the other ingredients stick together strongly.
Stabilizers: In traditional rammed earth construction,
the earth mixture can be stabilized using natural elements such as straw or lime.
However, in modern applications, cement may be added as a stabilizer to increase the strength and corrosion resistance of the mixture.
The exact proportions of these materials can vary,
but a typical mix may consist of 70% sand, 15% clay, and 15% gravel.
These proportions are often adjusted based on the specific land source,
the desired properties of the finished wall, and local environmental conditions.
How can we build using rammed earth?
Construction using rammed earth includes some basic steps that must be applied,
which we will mention below:
Preparation
Leveling the ground and laying the foundation before construction begins.
The foundation may be made of more flexible materials such as concrete, providing a base for the rammed earth walls.
Concrete pouring
Install two parallel panels of plywood to determine the thickness and shape of the wall,
so that the space between these panels is where the rammed earth will be placed.
Layers
Distribute a thin layer of the wet earth mixture between the boards.
The pressure
The ground must be compacted, preferably with a pneumatic ram.
Once the layer is compacted, its height can be reduced to half its original height,
ensuring a solid and dense structure.
Repetition
The layering and compacting process is repeated until the wall reaches the desired height.
Processing
Once the formwork is removed, the wall is left to dry and harden,
a process that can take from a few days to several weeks, depending on the climate.
By mastering basic principles and techniques,
builders can create structures that not only stand the test of time,
but also tell the story of the land from which they originate.
What are the advantages of building using rammed earth?
As one of the oldest construction techniques, rammed earth offers many benefits that make it increasingly important today for sustainable and resilient building solutions.
Its advantages extend to the environmental, structural and aesthetic areas.
Environmental benefits and sustainability:
Lower energy footprint
Compacted soil uses mostly local materials, reducing the need for transportation and associated energy costs.
This means that the energy footprint, from supply to installation, remains minimal.
Minimal waste production
Since the primary ingredients come from natural sources,
excess materials can be reincorporated into the environment without harmful effects.
Furthermore, the construction process itself has been simplified to ensure minimal waste.
Natural regulation
The high thermal mass of rammed soil naturally regulates internal temperatures,
reducing the need for artificial heating and cooling.
This leads to energy savings in the long term.
Durability and flexibility:
Long lasting
With the right precautions, rammed earth walls can last for centuries,
as historic structures around the world attest to their longevity.
Fire and pest resistance
Unlike many traditional building materials, rammed earth is inherently fire-resistant and an undesirable habitat for pests, ensuring greater safety and less maintenance.
Ventilation
Although the walls are strong, they are permeable to air,
ensuring good indoor air quality by allowing the structure to breathe, thus avoiding problems such as mould.
Aesthetic appeal and versatility:
Unique textures and colors
Rammed earth walls have a unique texture and color palette depending on the soil and aggregate used,
providing a natural, rustic and organic aesthetic that many find attractive.
Flexibility in design
While they have a traditional and earthy look, they can adapt to various architectural styles,
from more traditional to contemporary designs.
Audio benefits
Rammed earth walls can provide excellent sound insulation due to their density,
making spaces quieter and more peaceful.
Conclusion
In conclusion, the advantages of building with rammed earth are numerous,
as it provides a sustainable building solution without compromising on strength, durability or beauty.
For those looking for an environmentally friendly,
aesthetically pleasing and long-lasting construction method, rammed earth stands out as an ideal option.
