REBAR
REBAR ORDER
linft = (long_bars × L) + (short_bars × W)
ft
ft
RESULT
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FILL IN ABOVE
Sized for unreinforced and lightly reinforced slabs only. Slabs supporting columns, walls, or vehicles over 5,000 lb need engineered design. Verify cover (3 in from earth, 1.5 in from finished surface) per ACI 318.
About this calculator
This rebar calculator estimates the rebar grid for a residential concrete slab — driveway, patio, garage floor, or shed pad. Enter the slab length, width, the bar spacing on center, and the bar size (#3, #4, or #5 are common for residential slabs). The calculator returns the bar count in each direction, total linear feet, total weight, and the number of 20 ft sticks to order from the supply yard. Standard residential slab spacing is 18 in OC for patios and garages, 12-16 in OC for driveways carrying vehicle weight.