Australia’s first certified carbon neutral bricks have been launched by Brickworks Building Products, generating renewed interest in the use of bricks in the built environment.

Manufactured at Austral Bricks’ Tasmanian Longford facility, the bricks are fired using sawdust, a biomass material as well as a waste product of the forestry industry in Tasmania. According to Brickworks, using sawdust for the kiln allows the plant to release 215 tonnes of carbon dioxide annually – about the same as 12 average Australian households.

This is compared to the approximate 8,500 tonnes of carbon dioxide that would be released if a similar kiln was fired on natural gas.

An ongoing program of energy efficiency improvements to the plant’s operation has also worked to reduce emissions, including a new gas burner system, new lighting, and the use of recycled kiln heat to dry the sawdust.

“We’ve actually been firing that plant on sawdust for a number of years, thinking we were doing the right thing because we were using a waste product instead of natural gas,” explains Brickworks’ Group Technical, Research and Engineering Manager, Cathy Inglis.

“We hadn’t worked out the difference in carbon loads until about a year ago, when we saw the potential for this product. So, we went through every bit of the process from the beginning right through the end, to the last piece of paper; the manager’s car – you count all that in the certification process.”

The Government’s voluntary Carbon Neutral Programme requires all emission contributors, such as raw material extraction, onsite transport, product deliveries, water usage, and packaging, to be measured for the National Carbon Offset Standard (NCOS) certification. 

What has resulted for Brickworks is a plant producing bricks more energy efficiently than their traditional brick counterparts. However, there were still greenhouse gases, primarily within the transportation leg, that needed to be offset.

In response, the company purchases certified credits to ensure that the bricks are carbon neutral until they are delivered to site. This includes assisting in local Tasmanian projects such as tree planting under the Forest Alive program, which according to the NCOS, achieves abatement by “removing carbon from the atmosphere and storing it in soil and trees”.

Image: buildforliving.com.au

Although the product is barely a month old on the market, Inglis says that there has already been a surge in interest for the product from Australian architects.

“Bricks are one of the cheaper building materials to use, but they have a reputation of using a lot of energy to be made. As such, architects who were looking at projects with green credentials would steer away from bricks, but the availability of carbon neutral bricks gives them an opportunity to look at bricks again,” notes Inglis.

She adds that specifying the carbon neutral bricks might help projects earn credit points under the ‘Material’ section for the Green Building Council of Australia’s Green Star rating system, since utilising these bricks would mean no energy load on a building.

The bricks can also be used for thermal mass, which would reduce the ongoing heating and cooling requirements and costs for buildings.

Image: sourceable

Despite a current lack of evidence that there is, or will be, a rise in demand for the bricks, their ‘carbon neutrality’ points to a potential renewed interest in the material, not just for residential projects, but commercial applications as well.

This is particularly so as the costs of the carbon neutral bricks remain unchanged, with the bricks themselves retaining the same properties, equivalent strengths and appearances as all other clay bricks.

The stockpile at the Tasmanian operation

When asked if competitive products are expected to emerge, Inglis says other manufacturers will definitely consider the option of producing certified carbon neutral bricks, but must ‘put in the hard yards’ to guarantee the feasibility of its production in other places. 

“We’re looking at some of our other plants now to see if we can do the same thing. We’re starting with the Melbourne manufacturing site as the two new recently commissioned plants have already reduced the energy use by 45 per cent,” she says.

“But we can’t go and fire kilns all around the country on sawdust, because sawdust isn’t available everywhere. Transporting sawdust around the country isn’t economical – it’s got to be an economical balance in manufacturing decisions.”

The firm is currently undertaking trials to test if other biomass, organic waste materials can be substituted for sawdust, with an aim of continuing to drive down energy use of all its plants.

The carbon neutral bricks are available nationally under the Austral Bricks (Tasmania) and Daniel Robertson brand, a boutique range of bricks that was originally created for the Melbourne market.

Daniel Robertson bricks