How To Calculate Cement Sand for Plastering

In this article, we will discuss how to calculate cement sand for plastering.

  1. Introduction  

Plastering is the process of covering the rough surfaces of walls, columns, ceilings, and other building components with a thin coat of plaster to make the surface smooth and durable. 

Plastering on the externally exposed surface is called rendering.

  2. Ratio For Plastering  

For cement mortar ratio for wall, plastering is 1:6

For cement mortar ratio for ceiling, plastering is 1:4

The plastering shouldn’t be more than 12-15mm. Use good quality cement and sand for plastering.

  3. How To Calculate Cement Sand for Plastering?  

Let us take an area of 100 sqm.

The plastering thickness is about 12mm = 12/1000 = 0.012m

Volume of cement mortar required = ( Plastering Area x thickness )

= 100 m² x 0.012m = 1.2 m³

Take 35% Sand Bulkage and 20% wastage

Volume (with bulkage) = 1.2 m³ x (1+0.2+0.35)

= 1.86 m³

Cement : Sand (Ratio) = 1 : 6 ( Total = 1+ 6 = 7 Parts )

Cement required (1 Part) = 1.86 x 1/7

= 0.265 m³ /0.0347

= 7.66 bags (Approx – 8 Bags)

Sand required (6 Part) = 1.86 x 6/7

= 1.59 m³

  4. Objectives of Plastering  

a. To provide a smooth and finished surface.

b. To protect the surfaces against atmospheric effects.

c. To resist chemical actions.

d. To cover defects in the structure.

e. To give a decorative appearance.