Currently one of the fastest growing construction methods in the UK is building with ICF (insulated concrete formwork) blocks. With this method, walls are built with lightweight polystyrene blocks and then filled with concrete. The blocks are light and quick to build with, and the resulting structures are strong, durable, quiet and energy efficient due to the characteristics of the concrete and polystyrene. The most efficient way of filling the forms with concrete is to use a concrete pump.
For ICF buildings it is important to specify a large enough pump for the job – the concrete placing boom must be able to reach easily around all the walls. The concrete must be placed steadily and in layers so as not to cause damage to the blocks. Using good quality 10mm aggregate, the concrete can be placed more precisely with 75mm end hoses instead of the more usual 100mm hoses.
As you can see from the adjacent photo, the blocks used are engineered to fit together easily and securely. There are ties that connect the two sides of the blocks together to give them strength and to make fixing the reinforcing steel easy. For more information on the benefits to be gained from using ICF blocks you can read this Wikipedia page.