Fox Blocks ICF foundations are a simple solution to all building projects no matter how complex. Fox Blocks interlocking, light-weight expanded polystyrene concrete forms are a permanent part of the wall after the concrete is placed. Insulating capacity of expanded polystyrene coupled with the structural integrity of reinforced concrete is a powerful combination. Fox Blocks walls are stronger, safer, quieter and more energy-efficient. See our knowledgeable staff to help design an ICF foundation for your project today.