Step 20: Pouring Concrete
There are several things to keep in mind when pouring an ICF project. We go into detail in the Basic ICF Installer Training Course but for now, just know that pouring concrete walls are typically done in lifts. A lift is a specified height that concrete is poured to at any one time in a continuous pour. Concrete, when poured, will begin an initial set or slake. The timing on this will vary based on temperature, humidity, and other weather conditions, but is typically 30 to 45 minutes.
Working around the structure, ICF lifts are poured to a height of 4 feet. The initial 4-foot lift should reach the bottom sill of windows so that consolidation can be accomplished during the first lift. Once you reach where you first poured, continue pouring, repeating the process 4 feet at a time. This process is repeated until the full height of the ICF wall is reached.
Each lift should be internally vibrated into the lift below it. Vibrating concrete in this way returns the concrete to a semi-liquid state. It ensures that concrete is continuous by preventing voids or honeycombing in the wall.
