CHRYSALITH
Render of tufa-forming structure
Render of tufa-forming structure
Light microscope images of moss-tufa
CHRYSALITH is aN ARCHITECTURAL explorATION OF mosses that bind atmospheric CO2 and calcium into a form of bioconcrete called tufa (2025)
Tufa-forming moss Palustriella commutata, Staffordshire, UK
Project site: undercroft of concrete bridge in social housing project Thamesmead, East London
Tufa rock formed by moss
My latest project is a continuation of my research on biomineralization for carbon capture. It happened during my Masters in Bio-Integrated Design at the Bartlett, University College London.
I have been exploring mosses that bind atmospheric CO2 and calcium into a form of bioconcrete called tufa. Due to its porosity, tufa can soak up and store water which makes it a great habitat for a diversity of plants and microorganisms. Furthermore, tufa purifies water environments by adsorbing heavy metals and neutralizing substances like sulfuric and nitric acids from human activities. For six months I collaborated with a biologist to explore how carbon capturing architecture could be grown from tufa on site.
Tufa-forming moss relies on calcium. We conducted experiments on recycled concrete as a circular calcium source. Once conventional concrete has set, it can only be reused as aggregate, not however as a binder. Tufa-forming mosses could re-mineralize the aggregate with biocement.
We propose filling formwork modules sewn from natural fibres with ground recycled concrete. These modules will then be seeded with tufa-forming moss and suspended from cables to form huge structures. Rain water will be channeled onto them, gradually seeping through the ground concrete and dissolving the contained calcium. The tufa-forming moss will then bind this calcium with atmospheric CO2 into a carbon capturing bioconcrete.
The project is based in an unused under-bridge space in a social housing project in East London. At the heart of our proposed site transformation are structures, acting as scaffolds that gradually become biomineralised through tufa-formation. Creating a community space while capturing carbon. These structures are strategically placed beneath the bridge where site conditions favor shade and moisture retention.
Inspired by the movement of flowing water, the form of the structures is designed to support natural biomineralisation processes.
Biomineralisation of tufa-moss
Sun simulations informing placement on site
Water flow as structural inspiration