Expanded cork, construction waste and human urine feature in this roundup of brick alternatives, designed to reduce the masonry unit's embodied carbon footprint.
After concrete and steel, brick has become the latest focus for architects, designers and material researchers hoping to slash the emissions associated with building materials.
That's because bricks are generally made from clay ? a finite resource that needs to be mined and shipped around the globe ? as well as being fired in fossil fuel-powered kilns at temperatures of more than 1,000 degrees Celsius, often for several days.

Read: Six material innovations aimed at slashing concrete's outsized carbon footprint

This energy-intensive process generates not just a large amount of greenhouse gas emissions but also carbon monoxide and other dangerous air pollutants, especially in South Asia where kilns are often still powered by coal. To tackle these problems, brick manufacturers and researchers are increasingly looking at how to make use of local waste materials to create masonry units, as well as reverting to traditional methods of sun-drying to cut out the need for firing.
Read on for seven examples of brick alternatives, ranging from experimental student projects to the Dezeen Award-winning K-Briq, which is set to go into mass production this spring.

Cork blocks by MPH Architects, Bartlett School of Architecture, University of Bath, Amorim UK and Ty-Mawr
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