Precast tiles 'grown' from bacteria are three times stronger than traditional concrete blocks with just 5% of the carbon footprint
A precast concrete tile has been developed that is 'grown' biologically using a combination of recycled waste and biocement. The result is three times stronger than traditional concrete blocks, 20 per cent lighter and uses just 5 per cent as much carbon dioxide in its production, its manufacturer claims.
BioBasedTiles were developed through a new partnership between Dutch company StoneCycling, which creates building products from upcycled waste, and US-based biocement producer Biomason.
The product is intended for use on facades, interior walls and flooring, and comprises 15 per cent biocement and around 85 per cent waste material from granite production.
The biocement is used as a binder for the tiles and formed through a natural process similar to the way coral reefs grow, combining carbon and calcium at ambient temperatures to produce calcium carbonate, a biologically formed limestone material.
The technique is effectively a reversal of traditional Portland cement production, whereby carbon is liberated from limestone through intensive heating, emitting carbon dioxide as a byproduct.
Through a similar process, the tiles are grown in moulds as the biocement forms links between the grains of aggregate to strengthen the material from within. No warping occurs during production and the bacteria stop growing once production is complete.
StoneCycling co-founder Ward Massa tells RIBAJ: 'The tiles are grown at a microscopic level, we add food for the bacteria and the bacteria wake up and start combining calcium and carbon to create a limestone-like material between the pieces of granite waste.' It’s this process, he explains, that allows the product to become stronger than traditional concrete blocks.
Once released from moulds, tiles cure for 72 hours at room temperature before being shipped. They are available in a range of different sizes and three different tones/textures.
The largest installation of BioBasedTiles is at the Helix Lab Research and Education Center in the city of Kalundborg in Denmark. The interior flooring installation, for client AP Ejendomme, is estimated to have saved 2,865kg of CO2, while upcycling around 19,000kg of waste. BioBasedTiles were also installed in the new headquarters of Dropbox in San Francisco.
'These projects were part of our pilot phase,' says Massa. 'The subsequent launch of the product in the European market means we are working on a lot of new projects including a big office in Stockholm and various projects in the Netherlands.'
StoneCycling says it teamed up with Biomason to accelerate the use of sustainable building materials. The US R&D firm claims biocement will eliminate 25 percent of the concrete industry’s global carbon emissions by 2030. Its first factory in Europe will open in 2023.
Cement is currently responsible for around 8 per cent of all global emissions and the manufacture of 1kg of Portland cement releases approximately 1kg of carbon dioxide into the atmosphere. Around half of the CO2 comes from the calcination of limestone; the other half from the combustion of fossil fuels necessary to achieve high kiln temperatures.