Expansible reveal with frontal tear strip for plaster walls

Claim 1

In a wall structure including a support and a pair of separate slabs of plaster-like material cast in situ on said support, the combination therewith of a unitary elongated expansible hollow separator between said slabs: a. said separator having a front wall, a rear wall and opposite side walls; b. said rear wall including a pair of planar flanges for attaching said separator to said support with said front wall facing outwardly, said flanges respectively extending laterally in opposite directions, said side walls serving as screeds to establish the thickness of said slabs; c. the center portion of said rear wall being inwardly arched to allow movement of said side walls toward and away from each other in response to expansion and contraction of said separate slabs; d. said front wall being joined to the side walls by fracture webs of thinner cross-section than said front wall whereby said front wall forms a tear strip removable after said slabs are formed, said fracture webs being defined by inwardly beveled outer ends of said side walls, said front wall being substantially flush with said side wall outer edges so that upon removal of said front wall said separator is exposed only at the region of its hollow interior; and e. each said side wall being provided with an anchor means disposed intermediate said front and rear walls and extending laterally outwardly from that side wall, the outer end of each anchor being a T-head locking the side wall to its associated slab for conjoint movement therewith.