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Screed Calculator

Area, volume, bags, ready-mix tonnes and drying guidance

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Enter your floor size then click Calculate.

FLFlorida Building Code

References & Sources

Standards Cited
  • ACI 302.1R โ€” Guide for Concrete Floor and Slab Construction
    Defines screed/topping types, thickness requirements, and drying time guidance
  • ASTM C150 โ€” Standard Specification for Portland Cement
    Specification for cement used in screed materials
Formulas Used
  • Screed volume: volumeM3 = length x width x (thickness / 1000)
    Source: Basic geometry
  • Weight and bags: bagsRequired = ceil((volumeM3 x (1 + wastage/100) x density) / 25)
    Source: ACI 302.1R โ€” Densities: traditional 2200, liquid 2100, fast-drying 2200, fibre-reinforced 2200 kg/m3
  • Ready-mix tonnes: readyMixTonnes = wetVolumeM3 x 2.2
    Source: ACI 302.1R โ€” Average screed density of 2200 kg/m3 for ready-mix estimation
  • Bag coverage: coverage = bags x 0.4 / thicknessMm
    Source: ACI 302.1R โ€” ~0.4 m2 per mm thickness per 25kg bag
Key Assumptions
  • Screed densities: traditional 2200 kg/m3, liquid 2100 kg/m3, fast-drying 2200 kg/m3, fibre-reinforced 2200 kg/m3 โ€” ACI 302.1R
  • Drying time: traditional 1 day per mm, liquid 24-48 hours walkable, fast-drying 3-7 days, extended 1.5-2 days per mm for >50mm โ€” ACI 302.1R
  • Typical wastage allowance of 10% for screed โ€” Industry standard practice