These systems combine prestressed beams with either solid blocks or voided ‘pots’. The blocks or pots are supported on the bottom flanges of the beams. In situ concrete is used to fill the gaps between the beams and the in-fill units and to form a level floor surface.

This type of floor is widely used in the domestic market as the component units are light and easily handled on site. It has limited use in commercial applications as the span would be restricted to about 6 m for an imposed loading of 5 kN/mm².