Surkhi - a pozzolanic material, to make natural cement resistant to water.
Surkhi is a very ancient building material. In many parts of India, the use of lime and surkhi is a common practice. It is because Surkhi bonds well with lime and helps in the carbonation of lime. Many monuments, temples, forts, haveli, traditional homes use surkhi with lime for mortars and plasters. Other aggregates and admixtures are also present in such mixes, but the bond between surkhi and lime is exceptional. Surkhi is porous and can retain moisture, which can help in the early carbonation of lime. It is identified long ago and is a crucial factor in the traditional system. Fun Fact: Even the modern material innovations in cement are also trying to use surkhi (or other pozzolanic material) as an ingredient for cement to make it less disastrous to the environment (read more about LC3 cement). So, the question is, if it is such excellent material, then why should we not learn about the old, time tested combination of lime and surkhi and make good, sustainable homes to meet our needs?
This is a platform for sharing knowledge in natural buildings based on the traditional shelter-making methods in India. The age-old practice of using natural materials available from the surroundings in a way without causing harm to nature is revived. The addition of plant and animal derivatives made these homes durable for centuries.