Slab Reinforcement – Mesh, Chairs & Ties

A reliable slab reinforcement takeoff follows one rule: measure twice, order once. The calculator converts your slab area, bar size and spacing grid into dependable quantities using Steel kg/m² = 2 × (Bar kg/m ÷ Spacing); Chairs = Area; Tie Wire = Steel × 0.004, then adds the waste margin that experienced builders apply by default. Example: Ø12 @ 15 cm both ways: 2 × (0.888 ÷ 0.15) = 11.8 kg/m² - a 50 m² slab carries 590 kg of steel. Field tip: chairs every 1 m² keep top steel in place during the pour - stepping on mesh buries it. The result is broken down into purchasable units - bags, sheets, rolls or truck loads - so you can order the nearest whole unit without overbuying, and every figure traces back to the formula shown above.

1. 1

   Take dimensions

   Note the slab area, bar size and spacing grid for the area you are covering or filling.

2. 2

   Run the calculation

   The calculator applies Steel kg/m² = 2 × (Bar kg/m ÷ Spacing); Chairs = Area; Tie Wire = Steel × 0.004 the moment you type.

3. 3

   Check the breakdown

   Compare base quantity and waste-adjusted totals side by side.

4. 4

   Plan the purchase

   Use the final figure to price and schedule the delivery.

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