How to calculate cement, sand quantity for Plastering Cement Mortar Ratio for wall plastering 1:6 Cement Mortar Ratio for ceiling plastering 1:4 Plastering thickness should not be more than 12-15 mm. If there is a need for an additional coat don’t do that at one go. Ensure you are using good quality of cement & Sand (In silt content test, we have discussed how bad sand quality affects the work) Also, ensure you are using measuring box (not head pan) for site mix ( Here is the basic construction tools list) Please do read the plastering checklist post for the complete list. To calculate the cement and sand for 100 m2 plastering area in 1:6 ratio and 12 mm thickness Plastering thickness 12 mm = 12/1000 = 0.012m Volume of cement mortar required = ( Plastering Area x thickness ) = 100 m2 x 0.012m = 1.2 m3 (This is wet volume that means we need this much volume of cement mortar after mixing water, So for dry volume, we have to add 30-35% as bulkage of sand, we are using 35% and wastage as 20%) Consider 35% Sand Bulkage = 1.2 m3 x (1+0.2+0.35) (Many of us would use 1.54 as constant) = 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 (5 Part) = 1.86 x 6/7 = 1.59 m3 How much water required for plastering (1:4)-12mm thick Step 1:- Assumptions Area of Plaster = 100 m² Thickness of plaster = 12 mm =0.012 m Mix Ratio → 1:4 Step 2:- Volume of Plaster ∵Volume of plaster = Area of plaster x Thickness of plaster Volume of plaster = 100 x 0.012=1.2m³ Add 20% extra Quantity for Filling of joints, Depressions & Wastage ∴Volume of plaster = 1.2 + [ (20x1.2) /100 ] =1.2 + 0.24 =1.44m³ Dry volume of plaster = Wet volume x 1.35 Dry Volume = 1.44 x 1.35m = 1.944 m³ Step3:- Quantity of Cement Quantity of Cement = (Dry Volume of plaster x Cement ratio) / (Sum of the ratio) Quantity of cement = (1.944 x 1) /(1+4)= 0.3888 m³ ∵Density of Cement = 1440kg/m³ Weight of Cement = 1440 x 0.3888 = 559.872 Kg ∵ 1 bag of cement contains 50 kg of cement Number of bags = 559.872 Kg/50 = 11.2 No’s Step 4:- Quantity of Sand ∵ Cement : Sand :: 1:4 Quantity of Sand = Quantity of Cement x 4 ∴ Quantity of Sand = 0.3888 m³ x 4 = 1.5552 m³ ∵ 1m³=35.3147 Cubic Feet (CFT) Quantity of sand = 1.5552 x 35.3147 = 54.921 CFT ∵ 1 brass = 100 CFT Sand = 54.921 /100 =0.54921 Brass ∵ Density of sand = 1920 kg/m³ Weight of sand = 1.5552 x 1920 = 2985.98 kg ∵ 1 tonne = 1000 kg Weight of sand in Tonne = 2985.98 /1000 =2.985 Tonne Step 5:- Quantity of water Quantity of water equals to 20% Total Dry material (cement & sand) Quantity of water = 0.20 x (Weight of cement + Weight of sand ) ∴ Quantity of water = 0.20 x (559.872+ 2985.98) = 709.2 kg = 709.2 Litre

How to calculate cement, sand quantity for Plastering

Cement Mortar Ratio for wall plastering 1:6 

Cement Mortar Ratio for ceiling plastering 1:4 

Plastering thickness should not be more than 12-15 mm.

If there is a need for an additional coat don’t do that at one go.

Ensure you are using good quality of cement & Sand (In silt content test, we have discussed how bad sand quality affects the work) 

Also, ensure you are using measuring box (not head pan) for site mix ( Here is the basic construction tools list) Please do read the plastering checklist post for the complete list.

To calculate the cement and sand for 100 m2 plastering area in 1:6 ratio and 12 mm thickness

Plastering thickness 12 mm = 12/1000 = 0.012m 

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

                                                        = 100 m2 x 0.012m = 1.2 m3 

(This is wet volume that means we need this much volume of cement mortar after mixing water, So for dry volume, we have to add 30-35% as bulkage of sand, we are using 35% and wastage as 20%)

Consider 35% Sand Bulkage = 1.2 m3 x (1+0.2+0.35) (Many of us would use 1.54 as constant)

                                               = 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 (5 Part) = 1.86 x 6/7 

                                    = 1.59 m3

How much water required for plastering (1:4)-12mm thick

Step 1:- Assumptions

Area of Plaster = 100 m²

Thickness of plaster = 12 mm =0.012 m

Mix Ratio → 1:4

Step 2:- Volume of Plaster

∵Volume of plaster = Area of plaster x Thickness of plaster

Volume of plaster = 100 x 0.012=1.2m³

Add 20% extra Quantity for Filling of joints, Depressions & Wastage

∴Volume of plaster = 1.2 + [ (20x1.2) /100 ] =1.2 + 0.24 =1.44m³

Dry volume of plaster = Wet volume x 1.35

Dry Volume = 1.44 x 1.35m = 1.944 m³

Step3:- Quantity of Cement

Quantity of Cement = (Dry Volume of plaster x Cement ratio) / (Sum of the ratio)

Quantity of cement = (1.944 x 1) /(1+4)= 0.3888 m³

∵Density of Cement = 1440kg/m³

Weight of Cement = 1440 x 0.3888 = 559.872 Kg

∵ 1 bag of cement contains 50 kg of cement

Number of bags = 559.872 Kg/50 = 11.2 No’s

Step 4:- Quantity of Sand

∵ Cement : Sand :: 1:4

Quantity of Sand = Quantity of Cement x 4

∴ Quantity of Sand = 0.3888 m³ x 4 = 1.5552 m³

∵ 1m³=35.3147 Cubic Feet (CFT)

Quantity of sand = 1.5552 x 35.3147 = 54.921 CFT

∵ 1 brass = 100 CFT

Sand = 54.921 /100 =0.54921 Brass

∵ Density of sand = 1920 kg/m³

Weight of sand = 1.5552 x 1920 = 2985.98 kg

∵ 1 tonne = 1000 kg

Weight of sand in Tonne = 2985.98 /1000 =2.985 Tonne

Step 5:- Quantity of water

Quantity of water equals to 20% Total Dry material (cement & sand)

Quantity of water = 0.20 x (Weight of cement + Weight of sand )

∴ Quantity of water = 0.20 x (559.872+ 2985.98) = 709.2 kg = 709.2 Litre