4.10.3. Case Study 3: Cement Plaster with Waterproofing Additives – Coastal Housing Scheme, Kerala

Government low-cost housing near coastal areas of Kollam. Frequent rain and high humidity posed durability issues.

This chunk outlines the project's setting and the challenges it faced. The Coastal Housing Scheme was a government initiative aimed at providing affordable housing in a coastal region, specifically Kollam, which is known for its high levels of rainfall and humidity. These environmental factors create challenges for buildings, particularly concerning their durability and the longevity of finishes such as paint and plaster.

Imagine building a sandcastle at the beach. If it rains or the waves are high, the sandcastle quickly deteriorates. In the same way, the Coastal Housing Scheme faced durability challenges due to the coastal weather, which needed to be addressed for the houses to remain standing and looking good over time.

Early peeling of paint and dampness. Capillary water rise from foundations.

This section highlights the specific problems encountered during the project. One of the major issues was early peeling of the paint, which is often an indicator of underlying moisture issues in the building materials. Additionally, dampness indicated that moisture was rising from the ground, known as 'capillary rise,' which can lead to further structural issues if not properly managed.

Think of a sponge that absorbs water. If your sponge gets too wet, it will begin to leak, just like the houses started to show dampness and peeling when they absorbed too much moisture from the surroundings.

Used cement plaster with waterproofing admixtures on both sides of walls. Applied a polymer-modified slurry coat as a base.

Here, the solution to the identified issues involves the application of cement plaster that includes waterproofing additives. This type of plaster helps to prevent moisture from permeating the walls and causing damage such as dampness and peeling paint. Additionally, a polymer-modified slurry coat was applied as a base layer, which enhances the bond and provides additional waterproofing, ensuring better protection against the coastal climate.

Consider a raincoat that keeps you dry. By adding waterproofing to the cement plaster, the builders effectively created a barrier, much like a raindrop sliding off of a raincoat instead of soaking in. This ensures the houses stay much drier and more durable over time.

Walls showed no efflorescence or flaking after monsoon. Increased lifespan of interior paint and finishes. Reduced maintenance needs by over 50%.

The results of implementing the waterproofing additives in the plaster were quite positive. After the heavy rains of the monsoon season, the walls exhibited no signs of efflorescence (which is the white, powdery residue from salt deposits) or flaking, indicating that the moisture was being effectively managed. Furthermore, the lifespan of the interior finishes, like paint, was extended, and maintenance needs were significantly reduced, demonstrating the long-term benefits of the applied solutions.

It's like buying a high-quality pair of shoes that resist water. After a rainy season, if you notice your shoes still look brand new without cracks or stains, it means your investment paid off. Similarly, the structural integrity and aesthetics of these houses were preserved, cutting down the need for constant repairs.

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