Abstract: An isolation pocket form is placed on around a footing for a support column, and then covered with a lid which has a sharp peripheral rim extending upwardly. Concrete is then poured around and over the form and lid, forming an initially continuous concrete floor which can be used as a casting bed for making wall slabs. The sharp-bottomed grooves produced in the concrete by the rim are preferential fracture sites, so that, after the wall slabs have been removed, the concrete portion overlying the isolation pocket can easily and cleanly be broken out.

Abstract: An isolation pocket form includes a wall assembled from wall segments having reinforcing ribs. The form is secured to a floor with clips having projections which engage holes in the periphery of the form. A removable closure seats on an interior ledge of the form, the ledge being situated so that the top of the closure is flush with the top of the form. The closure is reinforced by a two-dimensional array of reinforcing ribs to give it strength and rigidity.