Black Cotton Soil Construction in Olkalao

Black cotton soil presents significant challenges for construction, especially in areas like Olkalao, Kenya, where it is prevalent. Arctic Space and Builders recently took on a complex project involving the remodeling of a house affected by the soil’s unique properties. This case study highlights the issues faced, our approach to solving them, and the lessons learned to help future clients and builders understand the importance of proper planning and expertise when building on such soil.

The Initial Assessment- Black Cotton Soil Construction in Olkalao

Our client, who was based in Dubai, reached out to us after noticing significant structural issues with their home, including cracks on the walls and floor. Despite the distance, we maintained constant communication through video calls, photos, and thorough documentation to keep the client informed every step of the way. Upon arrival at the site, our team conducted a thorough inspection and found that the house had been built directly on black cotton soil without sufficient foundational reinforcement. The soil’s natural expansion and contraction cycles had led to severe stress on the foundation, resulting in irreparable damage.

Key Observations:

• Cracks on Walls and Floor: The repeated expansion and contraction of the soil had caused cracks to develop throughout the structure.
• Foundation Instability: The foundation had shifted due to the soil’s poor load-bearing capacity and unpredictable behavior during wet and dry seasons.

Photos by Joe Photography

Deciding on the Best Solution

After continuous communication with the client and careful evaluation of the structure’s condition, it became evident that the house could not be salvaged in its current state. We decided to demolish the building entirely and install a new, reinforced foundation designed to withstand the challenges posed by black cotton soil.

Safe Removal and Reuse of Materials

Understanding the value of sustainability and cost-efficiency, we carried out a meticulous demolition process to safely remove materials that could be reused in the new construction. This approach helped reduce waste and provided savings for the client.

Materials Salvaged for Reuse:

• Bricks and blocks
• Roofing materials
• Doors and windows
• Select fixtures

Installing a New Foundation: Our Approach

Constructing a durable foundation on black cotton soil requires advanced engineering solutions. For this project, Arctic Space and Builders implemented the following measures:

1. Excavation and Soil Replacement: We excavated the existing black cotton soil to a significant depth and replaced it with a more stable mixture of murram and sand-gravel. This new base improved the load-bearing capacity and minimized future soil movement.
2. Reinforced Raft Foundation: A reinforced raft foundation was chosen for its ability to distribute the building’s load evenly over a wide area, reducing the impact of soil expansion and contraction. The slab was fortified with steel reinforcements to provide additional strength and resilience.
3. Moisture Barriers and Drainage Systems: To prevent water from infiltrating the soil and causing further expansion, we installed moisture barriers around the perimeter of the foundation. Additionally, a comprehensive drainage system was added to channel rainwater away from the building.
4. Elevated Structure Design: The new design included an elevated platform to reduce direct contact with the black cotton soil, further mitigating the impact of soil movement.

The Result

With these strategic measures in place, Arctic Space and Builders successfully constructed a new, stable foundation that could withstand the challenges posed by black cotton soil. The client, who remained involved throughout the process via video updates and detailed photos, was highly satisfied with the outcome, which not only restored the safety and functionality of their home but also ensured long-term structural integrity.

Lessons Learned and Recommendations

This project reinforced the importance of partnering with experienced construction professionals when building on problematic soils. Here are some takeaways for those considering construction on black cotton soil:

• Comprehensive Soil Testing: Always conduct thorough soil analysis to understand its properties before starting any construction.
• Choose the Right Foundation Type: Reinforced raft or pile foundations are highly effective for black cotton soil.
• Plan for Water Management: Proper drainage and moisture barriers are essential to control the soil’s expansion and contraction.
• Consult Experts: Engaging a team with expertise in managing soil-related construction challenges can save time, money, and stress.

Contact Arctic Space and Builders for Construction Project in Olkalao

If you’re planning a construction project in Olkalao or any area with black cotton soil, Arctic Space and Builders is here to help. Our experience ensures that your building is safe, stable, and built to last. We maintain constant communication with our clients, whether local or abroad, through video calls, photos, and proper documentation to keep you informed at every stage. Call us at +254 721 694346 for professional assistance and customized construction solutions.

Must Read:

• Black Cotton Soil Construction in Kenya