A PP suspended floor is a ground floor with a void underneath the structure. The floor can be formed in various ways, using timber joists, precast concrete panels, block, and beam systems, or cast in-situ with reinforced concrete. However, the floor structure is supported by external and internal walls. Supports underneath the floor are permanent and include sleeper walls or timber props placed at regular intervals. http://www.sjzwlplastic.com/pp-suspended-floor/