Compressed Earth Blocks/Bricks (CEB) House
Compressed earth bricks are eco-friendly construction materials made by compressing a mixture of locally sourced soil, sand, and water. The soil’s natural clay content acts as a binder, allowing the bricks to be formed without the need for firing, unlike cement bricks that require energy-intensive kiln-baking. The absence of cement in compressed earth bricks reduces their carbon footprint significantly. These bricks offer resource efficiency, cost-effectiveness, and thermal insulation, making them suitable for sustainable building. Their distinctive characteristics lie in their use of natural materials and minimal processing, providing a greener alternative to conventional cement bricks.
Step-by-Step Process for Making Compressed Earth Bricks:
- Gather the Right Soil: The first step is to find the right type of soil for making the bricks. The ideal soil should have a good amount of clay content (about 20-30%), which acts as the binder. Sandy or loamy soils can be mixed in as they act as stabilizers. Avoid using soil with high organic content, as it may decompose and weaken the bricks. The required clay content depends on the machine you are using so check with the manufacturer before you start. The machine you see in the picture below requires a very high clay content of nearly 80% or more.
- Soil Preparation: Before mixing, remove any rocks, debris, or large clumps from the soil. Break up the soil into smaller particles to ensure a more consistent mixture. This can be done using a shovel or hoe.
- Mixing the Ingredients: In a large container or mixing area, combine the soil and sand in the desired proportions. A common ratio is approximately 70% soil and 30% sand, but this can be adjusted based on the specific soil type and the desired characteristics of the bricks. Gradually add water to the mixture and mix thoroughly until it becomes a homogeneous, workable consistency. The mixture should be moist but not too wet. You may want to add a little bit of cement to add a chemical bond as well. This is suitable for areas where your bricks may be exposed to a lot of rain or other humidity.
- Loading the Machine: Now, you need a simple manual brick-making machine, which is usually made of metal. The machine has a mold that shapes the bricks and a lever or handle to apply pressure. Load the prepared soil mixture into the mold, making sure it is evenly distributed.
- Pressing the Bricks: With the soil mixture in the mold, pull down or push up on the machine’s lever or handle. This applies pressure to the soil, compacting it within the mold. The pressure helps the soil particles bind together, creating a solid brick shape. Depending on the machine design, you may need to repeat this step a few times to achieve the desired level of compression.
- Releasing the Brick: Once you’ve applied enough pressure, release the lever or handle. The compressed earth brick should now hold its shape within the mold. Carefully remove the brick from the mold and place it on a flat surface.
- Drying the Bricks: After making several bricks, move them to a well-ventilated and sunny area to dry. The drying process typically takes a few days, but it may vary depending on the climate and weather conditions. Turning the bricks occasionally during drying can help ensure uniform drying and reduce the risk of cracking.
- Curing the Bricks: After the bricks have dried, they need to be cured to gain strength and durability. Stack the dried bricks in a covered area or under shade and keep them slightly damp by sprinkling water on them regularly. This curing process can last for a few weeks.
- Ready to Use: Once the bricks have completed the curing process, they are ready to use for building purposes. These compressed earth bricks are eco-friendly, cost-effective, and suitable for constructing walls of houses, schools, or other structures.
Remember, making compressed earth bricks using a simple manual machine may require some practice to get the right soil mix and pressure application. However, it is a sustainable and empowering technique that has been used for centuries to build homes and communities around the world.
Adding windows, doors, and roofs
Adding windows, doors, and roofs to a structure made with compressed earth bricks follows general construction principles but may require some specific considerations due to the characteristics of the material. Here are some tips and things to watch out for when building with compressed earth bricks:
Adding Windows:
- Choose Appropriate Window Frames: Select window frames that are suitable for the size and weight of the compressed earth bricks. The frames should be strong and securely anchored to the surrounding structure.
- Ensure Proper Sealing: When installing windows, ensure they are properly sealed to prevent air and water leaks. Compressed earth bricks have porous surfaces, so proper sealing is crucial to maintain the indoor environment.
- Use Protective Coatings: Consider applying protective coatings or treatments to the window frames and sills to increase their durability and resistance to weathering.
Adding Doors:
- Strong Door Frames: Just like with windows, use strong door frames that can support the weight of the compressed earth bricks around the doorway.
- Hinges and Hardware: Choose sturdy hinges and hardware that can handle the weight of the doors and are appropriate for the construction material.
- Weather Stripping: Install weather stripping around the door frames to improve energy efficiency and prevent drafts.
Roof Construction:
- Structural Considerations: The roof design and materials should be chosen based on the structural requirements of the building and the local climate. Ensure that the roof can support the weight of the compressed earth walls.
- Waterproofing: Use appropriate roofing materials and ensure proper waterproofing to protect the compressed earth walls from water infiltration. Water can weaken the bricks and lead to structural issues.
- Overhangs: Consider adding overhangs to the roof design to protect the walls from direct rain exposure and minimize water runoff near the foundation.
General Building Tips:
- Foundation: A stable and well-designed foundation is essential for any construction project. Ensure the foundation is level and properly compacted to support the weight of the compressed earth walls.
- Proper Curing: Allow sufficient time for the compressed earth bricks to cure and gain strength before adding windows, doors, and the roof. Rushing this process may lead to settling and cracks in the walls.
- Good Drainage: Proper drainage around the building is crucial to prevent water from pooling near the walls. Poor drainage can cause erosion and water damage to the compressed earth bricks.
- Termite and Pest Control: Take measures to protect the building from termites and other pests that may be attracted to the natural materials. Use appropriate treatments or natural deterrents if necessary.
- Consult Experts: If you are not experienced in construction or working with compressed earth bricks, consider seeking advice or assistance from experts or experienced builders who are familiar with this building method.
By following these tips and paying attention to the unique characteristics of compressed earth bricks, you can ensure a successful and durable construction project. Building with these natural materials can create sustainable, energy-efficient, and aesthetically pleasing structures that blend harmoniously with the environment.
Benefits of Compressed Earth Bricks
Using compressed earth bricks and the building method of constructing with them offers several benefits, both for the environment and the communities involved in construction. Here are some of the advantages:
- Environmental Sustainability: Compressed earth bricks are made from locally sourced natural materials, primarily soil and sand, which reduces the need for energy-intensive production processes used for traditional bricks like firing clay bricks in kilns. This significantly lowers the carbon footprint associated with brick manufacturing, making it a more environmentally friendly construction option.
- Resource Efficiency: The method utilizes abundant soil resources, which are often readily available on-site or in the nearby surroundings. By using soil for construction, it reduces the demand for other building materials, such as concrete and cement, which require significant amounts of energy and natural resources to produce.
- Low Cost: Compressed earth bricks are cost-effective, particularly in areas where conventional building materials are expensive or not readily available. Since the main ingredients are soil and sand, which can be sourced locally, the overall construction cost is significantly reduced, making it a viable solution for affordable housing.
- Empowerment and Skills Development: The construction method of making compressed earth bricks is relatively simple and can be learned and implemented by local communities with proper training. This empowers people with skills for sustainable construction, giving them the ability to build their own homes and community structures.
- Thermal Insulation: Compressed earth bricks possess natural thermal properties that help regulate indoor temperatures. They provide better insulation compared to traditional bricks, reducing the need for energy-intensive heating or cooling systems.
- Breathability: The use of natural materials in compressed earth bricks allows the walls to “breathe,” allowing moisture to escape and preventing issues like condensation and mold formation. This contributes to a healthier indoor environment.
- Durability: When properly manufactured and cured, compressed earth bricks can be durable and long-lasting. They can withstand the stresses of building structures and have been used in ancient constructions that have stood the test of time.
- Reduced Construction Waste: Unlike other construction materials that generate significant waste during production, compressed earth bricks have minimal waste during manufacturing. Excess or damaged bricks can often be recycled back into the soil.
- Aesthetics: Compressed earth bricks offer a unique and earthy appearance, adding a distinctive charm to buildings. The natural colors and textures of the bricks can create visually appealing structures.
- Contribution to Local Economy: By using locally available materials and labor, this building method contributes to the local economy and fosters self-reliance within communities.
Overall, using compressed earth bricks and the associated building method provides a sustainable and socially responsible approach to construction. It offers a range of benefits, making it an attractive choice for eco-conscious and community-oriented building projects.