Formula of Natural Buildings
Most of the technology involved in doing Natural Buildings are centuries-old. They have grown through generations of trial-and-error by highly skilled Masons and Craftsmen. It is not a coincidence that ancient buildings have survived for so long without Cement or Steel. There are buildings that have withstood for ages, simply due to the fact that the artisans have the right understanding of the material property.
However, we have no hard and fast rule of how different construction materials need to be mixed, or in what ratio they are to be used. What ratio should organic additives like Kadukkai - Jaggery, or different types of gums be added to mud or lime?
The centuries-old buildings that we see today were all built with intuition and experience using a heightened sense of touch, smell, and feel.
The ancient craftsmen held immense empirical knowledge with numerous years of trying and failing and trying again. They developed a good feel of their materials. Through constant experimenting, they evolved an acute sensual experience. Slowly they intuitively perform work, that guides them better than analytical thinking. Hence, though artisans were empirically strong, they largely remained not so clear on why buildings stay durable from a scientific point of view.
There are no Standards
Any Natural Builder and Heritage Artisans will be aware of the fact that each and every local material from a place is unique and has different properties. The material properties also change with the way we treat them. For example, the mud left to ferment in water keeps increasing its clay content as the days pass, and we cannot strictly judge its fixed clay content. Similarly, we cannot put out a set, standard formula for any material.
While local houses and mansions were built with the most local materials possible, palaces and religious buildings were built with materials that were brought from hundreds of miles away, as certain materials from specific places had more desirable qualities. However, we cannot encourage over-utilizing any particular resource, but find a suitable way to strengthen what we have locally at hand.
Organic Construction Additives
Today numerous studies and researches are undertaken with different synthetic additives tested with typical cement mixes. These tests rooted in our organic and inorganic additives of ancient buildings.
Many agricultural products and by-products were blended into building materials. Cow based additives like dung and urine, Milk-based additives like curd and casein, Gums like aloe vera and Cactus, Rice Husk and Straw, Oils like Linseed and Mahua, Fruits like Wood apple, Barks like Teak and Kolamavu, Roots like Sweetflag, Resins like Babool and Guggul were used for different purposes.
Many admixtures were used in construction and mostly artisans never used a single organic admixture. It was a combination of two or three for them to react well, compensate each other’s shortcomings, and form a balance. Hence when used in the correct combination of different additives, they are in harmony.
Trial and Errors
Ancient Indian texts reveal to us certain hints that guide us in the right path. Texts like Samarangana Sutradhara, Apparjitha Pracha, Abhilashitartha Chintamani hint at the presence of different materials like ash, cow dung, curd, Cactus Juice, etc.
Still today, there are highly skilled masons, well skilled in the art of Natural Building in India from whom we can learn the art. We can try out different mixes and through observance and lab tests one can put their strengths to test.
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