Guidelines for Cement Usage

Standard Values

 

  • One ton of cement = 20 bags
  • One cubic metre of RCC (1:2:4) will require approximately 6 bags of cement.
  • Ten square metre of mosaic layer of average 12 mm thickness with cement to marble grit ratio (1:2) will require 2 bags of cement. 
  • Recommended mix ratios for construction are as shown
Construction Purpose Mix Ratios 
Brick masonry 9” inch thick or more1:6 (Cement : Sand)
Brick masonry 4” thick1:4 (Cement : Sand)
PCC (Plain Cement Concrete)1:2:4 (Cement: Sand: Coarse Aggregate)
RCC ( Reinforced Cement Concrete)Min. M20 Grade - 1:1.5:3 (Cement : Sand: Coarse Aggregate)

*All values indicated are standard recommendations

 

Cement PlasterMix Ratios
Interior Walls 1:5 (Cement : Sand)
Exterior Walls1:4 (Cement : Sand)
Roof Ceiling 1:4 (Cement : Sand)

*All values indicated are standard recommendations

Estimating Quantities

Quantities of cement, fine aggregate and coarse aggregate required for concrete with ideal water cement ratio.

Nominal Mix Water Cement Cement Fine Aggregate (Sand) Coarse Aggregate (Broken Stone)
C:Fa:Ca Ratio (by Weight) (in bags) (in cft.) (in cft.)
1:2:4 / M15 0.55 16 41.3 82.6
1:1.5:3 / M20 0.42 21.5 40.7 81.4
1:1:2 / M25 0.33 30.2 37.2 74.4

*All values indicated are standard recommendations

C - Cement

Fa - Fine Aggregate

Ca - Coarse Aggregate

  • Use the best quality cement.
  • Check week number and the year of manufacture of each lot. 
  • Cement must be stored on wooden planks and covered by plastic sheets for longer life.
  • Ensure that there is no clay in sand and aggregates. 
  • Prepare accurate mixes on the pucca floor.
  • Use the mix within 1.5 – 2 hours of adding water.
  • Use only potable water for construction uses. 
  • Fill up all the voids in shuttering before pouring the concrete. 
  • Use a mixture machine and vibrator for better results. 
  • Start curing after 12 – 16 hours of construction & continue till at least 7 days.
  • Don’t store the bags in a building whose walls, roof and floor are not moisture proof. 
  • Don’t use saline or impure water for construction work.