Inputs
Results
Enter your floor size then click Calculate.
NAIBC / IRC codes
References & Sources
Standards Cited
- ACI 302.1R — Guide for Concrete Floor and Slab Construction
Defines screed/topping types, thickness requirements, and drying time guidance - ASTM C150 — 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 — 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 — Average screed density of 2200 kg/m3 for ready-mix estimation - Bag coverage:
coverage = bags x 0.4 / thicknessMm
Source: ACI 302.1R — ~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 — 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 — ACI 302.1R
- Typical wastage allowance of 10% for screed — Industry standard practice