A concrete extruder comprising a frame that houses a reciprocating ram (25), a ram driving means, a mould (22) and a hopper (16), wherein concrete mix is received in the hopper and compacted through the mould under the force of the reciprocating ram; the ram driving means being hydraulically operated and including a drive which drives a hydraulic pump (24) to pump fluid to a hydraulic cylinder (32) that is coupled to the ram for reciprocally driving the ram.