Chairs of adjustable height for use in concrete constructions

Apparatus characterized as a chair said apparatus supporting, positioning and retaining a concrete reinforcing bar in place at predetermined height in the pouring and construction of concrete slabs beams at a jobsite wherein the concrete reinforcing bar remains as an integral element of the slab beam construction, which comprises

• a cap constituted of a tubular member having an upper face and a downwardly faced lower opening, the upper face of which is provided with a slot retaining and supporting the concrete reinforcing bar, the downwardly faced lower opening being formed by an enclosing side wall and upper wall forming a downwardly faced receptacle,
• a base containing an upwardly faced receptacle opening, and
• a stem having an upper terminal end and a lower terminal end, the upper terminal end of which can be fitted into the downwardly faced receptacle provided in the cap, the lower terminal end which can be fitted into the receptacle in the base, said stem being readily cut into desired lengths to provide a chair of adjustable height as predetermined by slab and beam thickness,
• whereby, said cap and said base can be shipped to a jobsite and a chair of needed height can be assembled therefrom by simply cutting the stem to a required length, and using said stem to complete formation of the chair based on requirements of slab and beam thickness.