To get to the composition that Maroun envisaged, a significant amount of research and development was necessary. In this he was assisted by a number of institutions, including the CSIRO and universities, such as UNSW. The end result? A lightweight masonry product (approximately 9kg) made from a by-product of power plant stations – coal ash – and chemical binding agents. It’s strong, durable and offers a range of benefits, including good thermal insulation.
‘The lighter weight is a real advantage for brick and block layers because you can increase your production and move onto another project,’ Mike explains. ‘Builders love the speed walls can be built, and the current price advantage offered by Nu-Rock provides them with a much needed profit margin. For homeowners, houses constructed with Nu-Rock are warm in winter and cool in summer, reducing the need to rely on heating and cooling systems.’
Along with a robust R&D process, Nu-Rock has also undergone rigorous testing, here and in the US, ranging from strength, leachability and water absorption to radiation and fire resistance.
‘We had fire tests show that on the one side of the block 1000°C was recorded, but the other side was only 80°C. That’s still hot but not something that would burn down,’ he adds. ‘The exterior would turn black [in a fire], but to come back to a house that’s completely black that you can paint over is a much better outcome than coming back to a home where you’ve lost absolutely everything.’
The company even gave thought to what would happen to the product at the end of its life cycle. Nu-Rock Australia successfully performed tests to crush the blocks and make them into new products, which went into recent housing projects. In the future this means a building can be knocked down, the blocks crushed up and used again on the new project or repurposed for another function.