A raised access floor panel with a replaceable insert is provided. The panel includes a cross-braced framework constructed of four side rail members, and at least one cross-brace member. The cross-brace member is connected to the rail members so that the cross-brace member spans an area defined by the rail members. A plate frame is connected to an upper edge of the framework. The plate frame has a centroid void area which is surrounded by a peripheral portion. The peripheral portion includes an inner margin and an outer margin. The outer margin has right-angled corner forming portions. The inner margin is formed with a Z-section profile having a web portion which is capable of receiving the panel insert in fitment with the plate frame so that the insert and the peripheral portion are capable of providing a co-planar working surface.