Plastering implies that any fixing is done to a wall or ceiling by adding a thin and usually cement plaster layer on top of it. Blunder creation and lightweight arches give the noise a heterogeneous appearance that makes it a good candidate both for bricks and painting. As regards to cement plaster, there are also lime plaster and clay plaster that can be applied to the interior wall surfaces.
Choosing the Ideal Plastering Material for Your Home
When choosing a plastering material for your home, two key factors come into play: surface protection and cost. Increasing the quality of plastering often raises prices, while prioritising lower costs can occasionally interfere with surface protection. Here’s what you should consider while making your decision:
Affordability: Pick the plastering materials that match your budget and give you the desired look.
Durability: Make sure the material used is able to resist all manner of extreme climatic conditions including up to the duration of the structure’s lifetime.
Workability: The task of finding affordable and durable materials that can be used in different kinds of weather should be your top priority.
Now let us find out the amount of basic components (i.e. cement, sand and water) needed for blended mortar plaster. Although the formula given in this blog is particular to cement plaster, similar rules can be used to determine the required amount of such material as plaster for any other material.
Qualities of the Ideal Plaster:
Adhesion: The plaster should attach properly to the background and stay in place under different weather conditions.
Affordability: It should be cost-effective and inexpensive to accommodate various budgets.
Strength and Durability: The plaster should be strong enough to resist time-wearing effect and mechanics throughout the operation.
All-Weather Application: It should be suitable for all weather conditions, maintaining consistent quality regardless of climate.
Moisture Resistance: Effective at preventing moisture penetration via surfaces, hence protecting the underlying structure.
Workability: Has good workability for ease of application and getting desired results.
Strength of Plastering – Nominal Mix
| Plaster Type | Table Header |
|---|---|
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12mm |
Applied on plain surface of brick masonry, typically 12mm thick.
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15mm
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Required for rough sides of 9” and 4.5” walls, applied at a thickness of 15mm.
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18mm
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Utilized for creating 'Dado' with cement concrete flooring, applied at a thickness of 18mm.
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20mm
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Applied in two coats on rough sides of walls or as per design specifications, 20mm thick.
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Calculating Cement and Sand Quantities for Plastering Work:
In plastering, the ratios of Cement and Sand are expressed as volumetric ratios (e.g., Cement:Sand = 1:5, meaning 1 part cement and 5 parts sand in the mortar mix).
Here’s how to calculate the quantities required:
Cement Volume per Bag: Each bag of cement weighs 50 Kgs or 110 lbs.
The volume of each cement bag is calculated as follows:
Volume = Weight of Cement / Dry Density of Cement = 50 Kgs / 1440 = 0.0348 m3.
Dry Density of Sand: The dry density of sand is 1600 Kgs/m3.
Plastering Process: Plastering is typically done in two layers: the first coat (rough coat or primary coat) with a minimum thickness of 12mm, and the second coat (finish coat or secondary coat) with a thickness of 8mm.
Total Plastering Quantity: The total quantity of plastering is the sum of the first coat and the second coat.
Now, armed with this information, you can proceed to calculate the exact quantities of cement and sand required for your plastering project.
Different Ratios of Cement Mortar for Plastering:
| Mix Ratio | Areas of Usage |
|---|---|
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1:6 & 1:5
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Internal plastering of bricks, providing a standard mix for general internal plastering purposes.
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1:4
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Suitable for ceiling plastering and external walls, offering a balance between strength and workability.
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1:3 |
Ideal for external walls subjected to severe climatic conditions, repair works, and where a richer mortar mix is necessary for durability.
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To calculate the quantity of cement and sand needed for plastering, follow these steps:
Find the total area of the wall to be plastered:
Total area = Wall width × Wall height = 10m × 10m = 100m².
Consider the ratio and thickness of plastering: First coat: Ratio of Cement to Sand = 1:5, Thickness = 12mm (0.012m).
Second coat: Ratio of Cement to Sand = 1:3, Thickness = 8mm (0.008m).
Calculate the total volume of plastering:
Total volume = Total area × Total thickness of plastering.
- For the first coat: Volume = 100m² × 0.012m = 1.2m³.
- For the second coat: Volume = 100m² × 0.008m = 0.8m³.
Find out the volume of cement and sand individually for both coats:
- For the first coat: Cement volume = Total volume × (1 / (1 + 5)), Sand volume = Total volume × (5 / (1 + 5)).
- For the second coat: Cement volume = Total volume × (1 / (1 + 3)), Sand volume = Total volume × (3 / (1 + 3)).
Calculate the total volume of cement and sand required for plastering:
Total cement volume = Cement volume of first coat + Cement volume of second coat.
Total sand volume = Sand volume of first coat + Sand volume of second coat.
You can plug in these values into the formulas to obtain the exact quantities of cement and sand required for your plastering project.
Step 1: Calculate the Area of Plastering
Area = width × height = 10 × 10 = 100m²
Step 2: Find the Wet Volume of Plastering
Wet Volume of First Coat = Area of Plastering × Thickness of Plastering
= 100m² × 12mm (Convert mm to m)
= 100 × 0.012 = 1.2m³
Hence, Wet Volume of First Coat of Plastering = 1.2m³
The Wet Volume of Second Coat = Area of Plastering × Thickness of Plastering
= 100m² × 8mm (Convert mm to m)
= 100 × 0.008 = 0.8m³
Therefore, Wet Volume of Second Coat of Plastering = 0.8m³
Step 3: Find the Dry Volume of Plastering
Dry Volume of First Coat = Wet Volume of First Coat × 1.33
= 1.2 m³ × 1.33
= 1.596 m³
Hence, Dry Volume of First Coat of Plastering = 1.596 m³
The Dry Volume of Second Coat = Wet Volume of Second Coat × 1.33
= 0.8 m³ × 1.33
= 1.064 m³
Therefore, Dry Volume of Second Coat of Plastering = 1.064 m³
Step 4: Finding the Individual Quantities of Cement and Sand:
First Coat Ratio = 1:5 (1 part Cement and 5 parts Sand)
Total Parts = 1 + 5 = 6
Quantity of Cement Required for First Coat:
= (Total Volume of First Coat Plastering × Number of Parts of Cement) ÷ Total Parts
= 1.596 m³ × 1/6 = 0.266 m³
Quantity of Sand Required for First Coat:
= (Total Volume of First Coat Plastering × Number of Parts of Sand) ÷ Total Parts
= 1.596 m³ × 5/6 = 1.330 m³
Similarly for the Second Coat:
Second Coat Ratio = 1:3 (1 part Cement and 3 parts Sand)
Total Parts = 1 + 3 = 4
Quantity of Cement Required for Second Coat:
= (Total Volume of Second Coat Plastering × Number of Parts of Cement) ÷ Total Parts
= 1.064 m³ × 1/4 = 0.266 m³
Quantity of Sand Required for Second Coat:
= (Total Volume of Second Coat Plastering × Number of Parts of Sand) ÷ Total Parts
= 1.064 m³ × 3/4 = 0.798 m³
Step 5: Finding the Quantity of Cement Bags:
Total Quantity of Cement = Quantity of Cement for First Coat + Quantity of Cement for Second Coat
Total Quantity of Cement = 0.266 + 0.266 = 0.532 m³
As mentioned, the volume of 1 bag of cement (50 kgs) = 0.0348 m³.
For 0.532 m³, the number of bags required:
= 0.532 × 50 / 0.0348 = 764.36 kgs = 15.28 bags
Similarly, Total Quantity of Sand = Quantity of Sand for First Coat + Quantity of Sand for Second Coat
Total Quantity of Sand = 1.330 + 0.798 = 2.128 m³
For Sand, 1 m³ = 1600 kgs. Thus, for 2.128 m³:
= 2.128 × 1600 = 3404.8 kgs = 3.4 tonnes
Step 6: Finding the Quantity of Water Required for Plastering:
The amount of water to add to the mix depends on the moisture content in cement, sand, and atmosphere.
Quantity of water = 20% of total dry material (Cement + Sand)
= 20% of (764.36 + 3404.8) = 0.2 × 4169.16 = 833.832 = 834 litres.
Final Result:
- Quantity of Cement Required = 764.36 kgs
- Calculated Quantity of Sand (Fine aggregate) Required = 3404.8 kgs
- Quantity of Water Required = 834 litres.
SRMP Cement is an excellent choice for a variety of reasons:
Quality Assurance: With SRMP Cement’s superior and standard qualities in plastering applications, you can rely on its consistent quality to provide dependable performance.
Strength & Durability: While using the SRMP Cement you can be sure that your wall will be effectively protected against the varying elements, even in harsh weather conditions as you enjoy long-term benefits of the walls.
Ease of Use: SRMP Cement has exceptional workability, allowing construction workers to apply and achieve required finishes more efficiently.
Cost-effectiveness: While maintaining high quality, SRMP Cement is reasonably priced, providing value for money without sacrificing performance.
Customer Satisfaction: SRMP Cement has established a reputation for meeting the demands and expectations of builders, contractors, and homeowners alike.
Calculating the amount of cement, sand, and water required for plastering is critical for any construction project’s efficiency and precision. By following the techniques provided in this guide, you may reliably identify the materials required for your plastering project, optimising resource allocation and reducing waste. Choosing the appropriate cement brand is essential for the success of your plastering project. To summarise, when it comes to plastering your walls, SRMP Cement provides not only exceptional quality and longevity but also peace of mind knowing that your project is in capable hands.
