Sustainable Earthen Housing System For Forcibly Displaced Population And Disaster Affected Areas

Earthen Housing

Introduction

Forced displacement has become one of the most pressing humanitarian and developmental challenges of the 21st century. According to the document, over 61 million people worldwide are reportedly displaced, including more than 21 million refugees. Africa alone hosts over 15.5 million internally displaced persons, accounting for nearly one-third of the global forcibly displaced population. These staggering numbers are driven by escalating conflict, violence, and natural disasters, all of which create an urgent demand for resettlement and sustainable housing solutions.

In addition to human-made crises, natural disasters such as floods, earthquakes, and storms continue to uproot millions, increasing the need for resilient, affordable, and rapidly deployable housing. While international and humanitarian aid often provides temporary shelter, the long-term goal must be adequate, safe, and sustainable housing that respects the dignity and rights of affected populations. The right to adequate shelter is not merely a matter of charity but a fundamental aspect of the right to an adequate standard of living.

The document argues that sustainable housing must meet several economic and ecological demands. It must be environmentally friendly, economically feasible, and socially inclusive. Among the various construction techniques available, earth-based building systems particularly rammed earth stand out as a prehistoric yet highly relevant solution. Today, about one-third of the world’s population lives in earthen housing, according to the United Nations. This makes earth not only a traditional material but also a contemporary answer to the challenges of resettlement and sustainability.

Why Earth? The Unique Properties of Rammed Earth

Rammed earth is a construction technique that involves compacting a mixture of earth, aggregates, and sometimes stabilizers like cement or lime into forms to create solid walls. The document highlights several distinct properties that make rammed earth superior to many conventional building materials.

First, rammed earth has high thermal mass. This means it absorbs heat during the day and releases it slowly when temperatures drop, acting as a passive heating and cooling system. This property reduces the need for artificial temperature control, thereby conserving energy and lowering utility costs. In refugee camps or resettlement communities where energy infrastructure may be limited, this is a game-changer.

Second, rammed earth is highly fire-resistant. Unlike wood or synthetic materials, earth does not burn, making it a safer option in areas prone to wildfires or arson. Third, earth is available almost everywhere. This local availability reduces transportation costs and embodied energy, two critical factors in sustainable construction. The document notes that the cost of constructing a rammed earth house can be less than two-thirds that of a standard frame house.

Fourth, the use of straw an agricultural waste product, is recommended to prevent shrinkage and cracking during drying. This not only improves the material’s performance but also promotes waste minimization and agricultural recycling. Stabilizing the rammed earth mix with a small amount of cement or lime can further improve material strength, durability, and resistance to weathering.

The Three Pillars of Sustainability in Earthen Housing

The document firmly grounds its argument in the three pillars of sustainability: environmental, economic, and social. Each pillar is addressed in detail, demonstrating how earthen housing satisfies all three simultaneously.

Environmental Conservation

Climate change is identified as the major environmental problem globally, causing temperature increases, flooding, storms, and landslides. Sustainable housing must be resilient to these extreme weather events. Rammed earth structures, when properly designed and stabilized, can withstand significant climatic stress. Moreover, the extraction of earth for construction is done well below the topsoil to protect agricultural capacity. The material is non-toxic, natural, and versatile, and its life cycle impact is favorable compared to concrete or steel.

Energy conservation is another key component. The document emphasizes reducing non-renewable resource consumption by using durable, local, and reusable materials. Rammed earth has low embodied energy compared to fired bricks or concrete blocks. Additionally, designing for deconstruction and recycling further reduces waste and environmental harm.

Economic Effectiveness

The housing industry significantly influences a nation’s economic capacity. By selecting local materials and labor, earthen housing projects can achieve economic effectiveness while creating local employment opportunities. The document stresses that using local solutions for the entire life cycle of a building from design to maintenance, contributes to community resilience and reduces dependency on expensive imported materials.

For forcibly displaced populations and disaster-affected areas, affordability is critical. Rammed earth housing costs substantially less than conventional construction, making it a viable option for governments, NGOs, and international agencies operating under budget constraints.

Social Participation and Cultural Adequacy

Social sustainability requires public participation and community inclusiveness. The document argues that housing solutions for vulnerable groups including refugees, immigrants, children, and the elderly must be developed with state support to ensure access to utilities and services. Moreover, housing strategies must respect cultural uniqueness and value. This includes protecting historical and cultural heritage and designing homes that align with local traditions and ways of life.

Earthen housing is culturally adequate in many regions because it has been used for millennia. Adobe, cob, and rammed earth are not foreign technologies; they are indigenous building practices that can be modernized without losing cultural relevance.

Sustainable Design and Green Building Principles

Sustainable buildings are not an afterthought; they must be planned from the earliest design stages. The document outlines the life cycle of a building, which begins with site selection and continues through design, construction, operation, maintenance, refurbishment, and finally demolition. At each stage, environmental impact can be minimized.

The stages of sustainable structural design are predesign, concept design, schematic design, detail design, and post-occupancy evaluation. The goal is to achieve expected structural performance while ensuring environmental protection. Green buildings take this further by applying life cycle assessment (LCA) to evaluate impacts from resource extraction to recycling.

The document notes that globalization has harmed the environment, but green building practices can reverse some of that damage. Non-renewable resources such as metals, minerals, fuels, water, land, timber, and clean air must be used efficiently. Earthen materials score well on these criteria because they are renewable, locally sourced, and biodegradable.

Technical Aspects of Rammed Earth Construction

For those interested in the engineering side, the document provides detailed technical specifications. Rammed earth has good compressive strength but poor shear and tensile strength. However, stabilization with cement or pozzolans can modify material properties, including absorption capacity, volume, strength, and durability. The most common advantage of stabilization is higher compressive strength and modulus of rupture, which resist erosion from weathering.

Moisture is the greatest enemy of unstabilized earthen buildings. Therefore, earthen materials should not be used for substructures like foundations, basement walls, or retaining walls. Protective measures include raising the building above flood levels, coating with renewable earthen plaster, and providing sufficient overhangs to deflect wind-driven rain. A small amount of cement stabilization is recommended to decrease environmental impact while improving durability.

In high seismic risk areas, special precautions are necessary. Earthen and tile roofs must be lightweight. The building layout should be regular in plan and elevation. Rigid diaphragm connections across intersections prevent separation during seismic shaking. Lateral restraints from timber, steel, or reinforced concrete can be used. Bracing elements must be distributed around the building perimeter to resist out-of-plane bending and torsional forces.

Reinforcement is critical in earthquake zones. The document recommends placing reinforcement at weak locations such as wall corners and openings. Thin reinforcement can be laid on mortar joints and secured into walls. Vertical and horizontal reinforcement helps control cracking. External mesh or mortar joint reinforcement prevents cracking and fall-off of wall pieces.

Material Properties and Design Specifications

The material properties of rammed earth vary based on the composition of the earth sample. According to NZS 4297 (1998), the modulus of elasticity ranges from 120 kPa to 20 GPa, depending on soil type. Compressive strength is around 0.5 MPa, tensile strength 0.02 MPa, and shear strength of steel-reinforced earth is 0.35 MPa.

Design specifications for rammed earth buildings in seismic zones include:

These specifications ensure that earthen housing is not only sustainable but also safe and resilient.

Structural Analysis and Findings

The document includes a sample analysis of a rammed earth building using finite element software (Etabs 2017). The model incorporated substructure (masonry wall) and superstructure (rammed earth wall). Load cases included dead load, live load, and seismic loads in X and Y directions (EQX+, EQX-, EQY+, EQY-).

The behavior factor (q) was calculated as 3.3 based on prEN-1998-1:2003 for medium ductility structural behavior. This factor approximates the ratio of elastic seismic forces to design seismic forces, ensuring satisfactory structural response.

Results showed that the structural response of a single-story rammed earth building is reasonable. Large moments were observed at material interfaces, corners, and openings. Therefore, the document recommends:

The deformed shape and stress distribution analyses confirmed that adding lateral load-resisting elements and stabilizers significantly improves performance under gravity and seismic loads.

Conclusion: A Path Forward for Resettlement

The document concludes that adopting green and sustainable materials like earth helps create a sustainable environment with minimal life cycle impact. Rammed earth construction is a traditional technology being improved due to its strength, durability, environmental compatibility, and affordability.

For forcibly displaced communities and disaster-affected areas, earthen housing offers a sustainable, economical, and environmentally friendly resettlement approach. However, when building multiple stories in earthquake zones, reinforcement must be placed at critical locations to enhance lateral load capacity and prevent drying cracks. Stabilizers further increase load-carrying capacity and material strength.

In summary, earthen housing is not a step backward into primitive living; it is a step forward into resilient, culturally appropriate, and ecologically responsible housing. For policymakers, humanitarian organizations, and engineers, this document provides a robust framework for action. By embracing sustainable earthen housing, we can shelter the vulnerable, protect the planet, and build a future where no one is left without a home.

Also Read: 28 Post-Neoliberal Housing Policy Ideas