Online Concrete Slab Calculator. Calculate concrete, reinforcement steel meshes, formwork, and billing for G+0/G+1 slabs.
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How to Use Slab Calculator
Enter the length, width, and thickness of the slab.
Enter rebar spacing and bar diameter to estimate reinforcement weight.
Input standard material prices to view the billing report.
Slab Concrete Volume calculations
Concrete volume is a direct cubic dimension calculation:
Volume = Length × Width × Thickness
Dry materials are then estimated using the M20 or M25 dry volume coefficient of 1.54.
Slab Reinforcement Grid specifications
Main reinforcement bars are laid along the shorter span, while distribution reinforcement is laid along the longer span. Standard residential rebar spacings range from 100mm to 150mm center-to-center.
Frequently Asked Questions
What is the standard thickness of a residential roof slab?
Residential building slabs are commonly designed with a thickness of 5 inches (125mm) or 6 inches (150mm).
What is clear cover for slabs?
Standard clear cover for concrete slabs is 15mm to 20mm to protect reinforcement steel mesh from rusting.