How Many Cement Bags Per Square Metre for Plastering | Cement Plastering | Cement Mortar Ratio | Plastering Work | Cement Consumption in Plaster

Introduction of Cement Plastering:

• Cement plastering is the process in which the cement mortar is applied to the surface of the wall to protect it from the penetration of water and other aggressive environmental conditions.
• In this article, we will see how to calculate the amount of cement & sand required for plastering and how to calculate the cement sand quantity for brickwork.
• The cement mortar ratio which is generally used for the plastering depends upon the type of plastering work.
• There are various types of cement mortar ratio are used for different types of cement plaster design.
• The plastering ratio which is recommended for the plastering of the plane surface, the rough surface of the brick wall, and the rough surface of the concrete walls and ceilings are 1:6, 1:4 and 1:5, and 1:3 are used respectively.

Also, Read: What Is Plaster | Requirement of Good Plaster | Types of Plasters

How Many Cement Bags Per Square Metre for Plastering?

Step 1: Volume of Plaster.

Here we will calculate the cement consumption in plaster for a 1 square metre area.

Let us take the plastering thickness for the surface of the brickwork is 12mm in a ratio 1:6(cement : sand).

First upon we have to calculate the volume of the cement mortar which is required for the plastering work of one square metre area.

Volume of Plaster = L x B x t

Here,

L = Length of the plastering surface= 1 m

B=  breadth of the plastering surface= 1 m

t = thickness of the plaster= 12 mm = 0.012 m

Volume of Plaster= 1 x 1 x 0.012

  Wet volume of Plaster = 0.012 m³

Step 2: Dry Volume of Plaster.

Here we have to calculate the dry volume of the plaster in order to find the consumption of the cement for the plaster.

Dry Volume of Plaster = 1.33. x wet volume of the plaster

Dry Volume of Plaster = 1.33 x 0.012

Dry Volume of Plaster = 0.01596 m³

Note: The Dry volume of the plaster is calculated and used in the formula because the quantity of the cement we are calculating is in the dry state.

Step 3: Volume of Cement in M³.

The Cement calculation formula for plastering are as follows.

Volume of Cement = ( Ratio of cement/Sum of the ratio of cement and sand ) x Dry Volume of Plaster

Volume of Cement = (1 / 7) x 0.01596

Volume of Cement = 0.0028 m³

Step 4: Volume of Cement in Bags.

Hence, the number of cement bags calculated are as follows.

Number of Bags = Volume of Cement/Volume of One Bag of Cement

Number of Bags = ( 0.0028/ 0.0347)

Number of Bags = 0.08 bag

We know that,

• The volume of one bag of cement is 0.0347 m³

Step 5: Volume of Cement in Kg.

Calculating the cement consumption for the plastering work in kg.

Volume of Cement in Kg. = Density of Cement x Volume of Cement 

Volume of Cement in Kg. = 1440 x 0.0028

Volume of Cement in Kg. = Density of Cement x Volume of Cement 

Volume of Cement in Kg. = 4.032 Kg 

We know that,

• The density of cement is 1440 kg per m³
• There are 0.08 cement bag is required for the plastering work of one square metre.

How to Calculate the Cement Sand Quantity for Plastering?

The method of calculating the quantity of cement and sand which is required for the plastering work is as follows.

Also, Read: Difference Between Gypsum Plaster and Cement Plaster | What Is Gypsum Plaster | What Is Cement Plaster

How to Calculate Plastering Quantity?

First upon calculating the total area where plaster has to be applied.

Then calculate the wet volume of that area where plaster is to be applied.

Wet volume of plaster = Area of Plaster x Plastering Thickness

We have to calculate the dry volumes of the plaster. The formula to calculate the Dry volume of the plaster are as follows.

Dry volume of plaster = 1.33 x Wet volume of Plaster

To calculate the quantity of cement.

Cement = (Ratio of Cement Sum of Ratio of Cement and Sand) x Dry Volume of Plaster

Here we will get the quantity of cement in m³ and we can calculate the consumption of cement for plastering work by dividing the total cement quantity by the volume of one cement bag.

After that, we have to calculate the quantity of sand required for the plastering work.

Sand quantity = (Ratio of Cement Sum of Ratio of Cement and Sand) X Dry Volume of Plaster

Here we will get the quantity of sand required for the plastering work.

Also, Read: What Is Gypsum Plaster | Advantage and Disadvantage of Gypsum Plaster

How Much Cement in 1 Cubic Metre Brickwork?

Here we will calculate how much sand and cement for brickwork.

• The size of the modular brick is 190 x 90 x 90 mm.
• Mortar Thickness is 10mm.
• Assume required brickwork volume is 1 cubic metre (m³).

Also, Read: Rate Analysis of Plastering Calculator | What is Rate analysis of Plaster | How to Use Calculator

How to Calculate Quantity of Cement Mortar in Brickwork and Plaster?

• The brickwork consists of bricks and cement mortar.
• So firstly we have to find the volume of bricks with mortar thickness and the volume of bricks alone.

Volume of Bricks with Mortar.

Size of Brick without mortar = 190 x 90 x 90 mm

Volume of 1 brick with mortar = 200 x 100 x 100 mm

(by taking 10 mm mortar thickness on all sides)

So that the number of bricks required for 1 cubic metre is as follows.

Bricks Qty = Calucrtion Area/ Volume of 1 Brick with Mortar.

Bricks Qty. = 1/0.002

Bricks Qty. = 500 nos

Here,

• Volume of 1 brick with mortar = 0.2 x 0.1 x 0.1 m
• Volume of 1 brick with mortar = 0.002 Cu.m. (m³)
• The Volume of brick with mortar = 0.002 Cu.m. (m³)

There are total 500 number of bricks are required for the construction of the one cubic metre brickwork.

Also, Read: Plaster Calculator | How to Work Plaster Calculator | What Is Plaster Calculation | How to Plaster Calculation for Wall

Volume of Bricks Without Mortar.

• Volume of 1 brick without mortar in mm = 190 x 90 x 90 mm
• Volume of bricks without mortar in m= 0.19 X 0.09 X0.09.
• Volume of 1 brick without mortar in cubic metre   =  0.001539 Cu.m. (m³)
• Volume of 500 bricks without mortar in cubic metre = 500 X 0.001539 Cu.m. (m³)
• Volume of bricks without mortar for 1 cubic metre= 0.7695 Cu.m. (m³)

Also, Read: Types of Plaster Finishes (List of Plaster Finishing)

How to Calculate Cement Consumption in Brickwork?

After that, we have to calculate the amount of cement mortar required for brickwork

• Required Amount of Cement Mortar = 1 m³ – Volume of Bricks without Mortar
• Required Amount of Cement Mortar = 1 – 0.7695
• Required Amount of Cement mortar  = 0.2305 Cu.m.  (m³) (Wet Condition)

The volume is in a wet state so that we need 0.2305 cement mortar in mixed condition (after adding water). In order to calculate the dry volume, we have to multiply 33 % as bulkage of sand.

• Dry Volume of a Mortarr = Required Amount of Cement mortar x [(100 + 300) %]
• Dry Volume of a Mortar = 0.2305 m³ x 1.33
• Dry Volume of a Mortar = 0.306565 m³

We know the cement mortar ratio for brickwork is 1:6 (where the 1 part is of Cement and the 6 Part Sand).

The sum of this cement sand Ratio is = 1+6 = 7.

• Required Amount Cement Quantity in Brickwork = Dry Volume of a Mortar x Cement Sand Ratio x Density of Cement 
• Required Amount Cement Quantity in Brickwork = 0.306565 x 1/7 x 1440 kg
• Required Amount Cement Quantity in Brickwork = 63 Kg
• Required Amount Cement Quantity in Brickwork = 63 kg/ 50 kg ( Cement Bag Weight)
• Required Amount Cement Quantity in Brickwork = 1.26 bags
• Required Amount of Sand = Dry Volume of a Mortar x Sand Cement Ratio
• Required Amount of Sand = 0.306565 x 6/7
• Required Amount of Sand = 0.26277 Cubic metre (m³)

So for the construction of 1 cum of brickwork, we need

• 500 Numbers of brick.
• 63 kg of cement.
• 263 m³ of sand.

Also, Read: Definition Related for Plastering Work | Tools For Plastering | Preparation of Background for Plastering

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