K-Briqs contain 90% certified construction waste and are made without the use of a kiln, to challenge traditional bricks with just over one tenth of their embodied carbon
The first commercial production line for an eco-friendly brick with around one tenth the carbon footprint of a regular brick is due to start operation in Scotland later this year.
The facility, which is run by Kenoteq, a start-up company set up by engineers from Heriot-Watt University, will initially manufacture 10,000 ‘K-Briqs’ a day and scale up to produce a total of over 2 million bricks in 2022.
K-Briqs are made of 90% certified construction waste and are formed without the need for a kiln, radically reducing their embodied energy.
Provisional calculations of embodied energy, which BRE is assessing for an Environmental Product Declaration, show an average 72.5 grams of CO2 per brick, or 13% of the embodied carbon of a traditional clay-fired brick (570g based on figures from the Brick Development Association).
‘Once we scale up to commercial production, we anticipate this figure will reduce to under 5%, a huge reduction in embodied carbon and energy,’ said professor of geotechnical and geo-environmental engineering at Heriot-Watt, Gabriela Medero, who set up the company with civil engineer Sam Chapman in 2019.
K-Briqs can be used in most exterior/facing brick applications as a replacement for traditional clay or concrete bricks, although initial applications are restricted based on British Board of Agrément (BBA) guidance. However, it is anticipated that they will soon be able to be used anywhere that traditional bricks are used.
Each unit has double the thermal insulation of Portland cement and is lighter than a traditional brick. Different colours are available and further colour and sizing options will be added to the range over the coming year.
It will take just 24 hours from the receipt of certified waste material to finished bricks leaving the factory gate. The low carbon manufacturing process is akin to concrete production, but without the cement, and bricks are moulded rather than fired. However, the specific details of the process are being kept confidential.
Kenoteq claims the entire UK annual brick demand could be met by a technology like K-Briq if circular economic processes were more established and recycled waste materials made better use of.
‘It is anticipated that construction and demolition volumes will double in the next 30 years, during which time the industry will be required to recycle more and more,’ said Medero.
The firm is working with the Construction Scotland Innovation Centre to develop several demonstrator builds, ready for COP26 in Glasgow this November. It is also in discussions to deliver other small-scale demo projects around the UK, details of which will soon be available.
K-Briqs were due to feature in this year’s Serpentine Pavilion, designed by Counterspace, but Kenoteq says the constraints of the programme design phase meant more traditional established solutions were ultimately specified.
Read more about bricks made using construction waste as used in Mae's Sands End Art and Community Centre.