Imagine spending thousands of dollars on a beautiful new exposed aggregate driveway or a massive concrete slab for your dream shed. It looks fantastic for the first six months. But after a wet Adelaide winter, you notice a hairline crack. A few months later, that crack is half an inch wide, and one side of the slab has visibly sunk. What went wrong? The concrete mix was fine. The pour was perfect. The failure happened long before the concrete truck ever arrived. At BT Concret