Sharing a failure case: The Hidden Impact of Painting Mangalore Tiles

I want to share a personal experience that turned into a valuable lesson for many painters.

We have Mangalore tiles (Hanchu) on our small portion on our terrace. These clay tiles serve a crucial purpose—keeping the space below cool, much like how water stored in earthen pots (ಮಣ್ಣಿನ ಮಡಕೆ) stays naturally cool.

                                                   Managlore tiles on a house               Photo Courtsey: Wikipedia

Painting these tiles is a common practice; major brands like Asian Paints offer specialized products such as Tile Guard for this purpose. Although painting sloped surfaces is very difficult, painters routinely do it as part of the building painting process.

The Unexpected Discovery

During one such painting job in our building, some tiles were mistakenly broken due to the difficulty of working on a sloped surface. These were replaced with new, unpainted tiles. That’s when something unexpected happened.

The Eureka Moment

Sitting under these tiles, I noticed that the usual cooling effect was missing, but I didn’t immediately connect the dots. One day, while splashing water on the tiles, I made a striking observation:

• The unpainted tiles absorbed water instantly.
• The painted tiles did not absorb the water, making it stay on the surface like plastic.

This meant that painting had altered the thermal properties of the tiles, turning them into insulators and negating their core function—providing a cooling effect.

Sharing failed experiences

I demonstrated this to a painter by splashing and spraying water on both painted and unpainted tiles. He immediately understood the difference and admitted that no engineering contractor or supervisor had ever pointed this out.

Later, when he was assigned a large house with Mangalore tiles to be painted, he explained this to the owner, who chose not to paint the tiles. The result?

✔ The owner saved money.

✔ The painter’s job became easier.

✔ The tiles retained their natural cooling properties.

Why I’m Sharing This

I personally lost significant money, time, and effort in this process, but I believe sharing this knowledge can prevent others from making the same mistake, as it is very common for painters to paint such tiles. If you or someone you know is considering painting Mangalore tiles, think twice.

During an evening walk, I spoke to a Civil Engineering graduate who had recently passed out of college and was starting his career as a contractor. Even he was surprised by this discovery and made note of this failure case.