The precast stair tread assembly frames into a wide-flange steel beam supporting the concrete floor slab edge. A continuous 1/4" x 4" flat bar runs between stringers, fastened with two 5/8" diameter by 1 1/2" A325 tension-control bolts placed within 4 inches of each stringer. A continuous structural angle sized 3x3x1/4 for spans up to 1 1/2" or 5x3x3/8 for spans from 1 5/8" to 3" supports the stair stringer from the wide-flange beam. Concrete fill is placed by others after the stair installation. Fillet welds of 3/16" size secure the flat bar and stringer connections.
Ø MIN. 3 1/128" MAX. 2" PRECAST TREAD (B/O) SEE S1Ø3 STRINGER 1/4 X 1Ø (UNO) 1/4''x4'' FLAT BAR CONT. BETWEEN STRINGERS W/ (2) 5/8"Ø x 1 1/2'' A325 T.C. BOLTS ( (1) BOLT W/IN 4'' OF EA. STRINGER ) 1 1/4" . DIM. PT. . 3/16 2 1/2 EDGE OF SLAB WF BEAM BY OTHERS CONCRETE FILL BY OTHERS AFTER STAIR INSTALLATION 3x3x1/4 (Ø TO 1 1/2'' SPAN)5x3x3/8 (1 5/8'' TO 3'' NOSING F.B. TO STRINGER 3/16 3
Members view this detail in full resolution, download the CAD files (SVG, PDF), and can adapt it in the built-in CAD editor — export DXF, DWG, or PDF.
Start membership