A tie assembly for use during construction of monolithic cast-in-place concrete floor slabs bearing on a masonry stem wall. The tie assembly connects to one or more header blocks of the stem wall, and the tie assembly is configured to retain a concrete form member in place during the pour and curing period of the cast-in-place concrete. The tie assembly has a removable tab member with one or more slots for receiving a wedge stake, which braces the form member against lateral forces caused by the wet concrete. A mechanical fastener is driven through an upper portion of the wedge stake and concrete form, and the insertion tip of the mechanical fastener connects to a reinforcement holder for retaining a reinforcing member in place.