Reimagining Construction: Innovating Cement-Free Building Methods

At Solarpunk Futures we are embracing a cement-free approach to create a harmonious and sustainable built environment. By using bricks made from industrial waste we are building structures that are naturally cooler and more durable, aligning our architecture with the rhythms of nature while reducing our carbon footprint.

Written by Shivangini Tandon and Kshitija Mruthyunjaya

When we envisioned our first Solarpunk Futures building in Goa, we knew it had to be concrete-free. This decision was a response to a startling reality: cement production alone contributes to major habitat destruction and 8% of global CO2 emissions [1]. We began a quest to identify materials that would cool us down in the intense summer heat, make us feel at home in the monsoons, minimise waste, last for generations, and reduce our CO2 emissions. The most common building material in the world, Portland cement-based concrete, serves none of these functions.

Cement production is an environmentally taxing process, from the quarrying of limestone to the final packaging of the product. The journey involves energy-intensive grinding and mixing of raw materials, followed by heating them to extreme temperatures in fossil fuel-powered kilns. This process not only scars landscapes and pollutes air and water but also releases substantial amounts of CO2, contributing significantly to climate change. The resulting cement, while ubiquitous, offers poor thermoregulation, failing to meet our needs for comfort and longevity.

By rejecting (Portland) cement, we opened the door to explore materials that align with our vision of sustainable, climate-responsive architecture. Over the last three years, we have explored various options including rammed earth, a technique using compacted natural soil; adobe, which are sun-dried mud bricks; and cement replacements like industrial by-products such as fly ash or slag.

Our search led us to our collaborator, Greenjams, who has developed a promising solution: their innovative binder (BINDR) and Agrocrete® bricks. This transformative building material is made using agricultural by-products or industrial wastes as substitutes for traditional aggregates and cement. Here in Goa, we're using waste from a furniture factory and excavated soil from building sites to create these bricks. By repurposing waste that might otherwise be burned or sent to landfills, our bricks offer a dual environmental benefit: reducing the carbon footprint of construction materials and providing a sustainable solution for waste management.

Left: Solarpunk Futures production Unit in collaboration with GreenJam in North Goa, Right: Agrocrete® bricks

Clockwise: Bindr from Greenjams, a non-cement mortar mix getting ready, wall tests at the factory

Agrocrete® bricks can be used for various construction purposes, including load-bearing walls, partitions, and other structural elements in buildings. Their production process consumes less energy and emits fewer greenhouse gases compared to conventional concrete blocks, making them a compelling option for environmentally conscious builders and developers. These innovative building blocks are not just a material substitute; they represent a paradigm shift in how we approach construction and its environmental impact. Over the last year, Solarpunk Futures has been working with Greenjams to develop and test versions of these bricks that can be used for various purposes in our projects. To match the versatility of traditional concrete we have been iterating on the bricks and putting them through tests in different contexts and conditions.

We have conducted a series of experiments with Agrocrete® and Bindr to test its strength and versatility. We began tests with this wall on the left built at our production facility.

Agrocrete® and Bindr was then used to build planter boxes at Villa Marina, North Goa.

Solarpunk Futures has teamed up with the Forca Goa Foundation, to transform the Guirim football ground into a vibrant hub of sustainable infrastructure and community engagement. We are currently building store rooms and a cabin using Agrocrete® and Bindr.

In our increasingly hot and humid climate, traditional reinforced cement concrete structures often struggle, absorbing heat and degrading faster due to moisture. Agrocrete® bricks, on the other hand, offer better thermal regulation. This means buildings that are naturally cooler and more durable, reducing the need for energy-intensive air conditioning and frequent repairs.

However, like any innovative building material, Agrocrete® bricks face their own set of challenges. Ensuring consistent quality across production batches, optimising on costs and manufacturing processes, and gaining acceptance in a traditionally conservative industry are ongoing hurdles. Our team continues to work on refining these materials and demonstrating their long-term viability as alternatives to traditional concrete.

As we push forward with our research and implementation, we're driven by the knowledge that the choices we make today will shape the environmental legacy we leave behind. By embracing sustainable alternatives we are continuously striving to reduce the ecological footprint of our built environment.

Further Reading : 

Cement:

UK Green Building Council’s neat little breakdown of the problems with cement and how to manage it’s ecological footprint https://ukgbc.org/our-work/topics/embodied-ecological-impacts/cement/

About Greenjams:

Visit greenjams.org