How Many Bags of Concrete Do I Need?

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How Many Bags of Concrete Do I Need

How Many Bags of Concrete Do I Need?

Important Point

Bags of concrete is required according to the requirement of the concrete. Bags of concrete depends on the size of the structure, if the concrete requirement is more then we need more bags of concrete and if the concrete requirement is less then we need less amount of concrete bags.

In the example of for 10’ x 10’ x 5” slab is below

Method – 1 

  • The weight of concrete= [(10 x 10 x (5)/12] x 133.34 = 5556 pound= 2520 kg
  • If the weight of concrete is 40 kg, the number of bags required= (2520/40) = 63 nos.
  • If the weight of concrete is 40 lb, the number of bags required= (2520/18.14) = 140 nos. (1 lb = 0.45 kg)

Method – 2

Step-1: Calculate Volume of Concrete Required Pouring 10 X 10 Slab Thickness  4 inch

The calculation of volume of slab is the multiplying of length, width, and thickness.

Example:

Let’s consider 10′ x 10′ slab with thickness 4”

  • Length= 10 feet
  • Width= 10 feet
  • Thickness= 4”
  • Volume of concrete= L x B x T
  • Volume of concrete = 10 x 10 x (0.33)
  • Volume of concrete = 33.00 cu. Ft……….(Because 12” = 1 feet, 4/12 = 0.33 feet)
  • It is equal to 0.23 cu. Meter or 0.3 cubic yard.

Explanation:

  • 3 ft= 1 yard, 3ft x 3 ft x 3ft = 1 yard x 1 yard x 1 yard
  • 27 cubic feet = 1 cubic yard
  • After that, we divide 33 cubic feet by 27 to get the volume of concrete in the cubic yard.
  • Volume of concrete = 33/27 = 1.22 cubic yard

Step-2: Adding 10% of Extra Volume

  • Now we are adding 10% of extra volume because of dry volume and wastage of concrete.
  • 1.23 x 10% = 1.23 x (10/100) = 0.122 cubic yard
  • So, the total volume of concrete = Original Volume + Extra Volume = 1.23 + 0.122 = 1.35 cubic yard

Step-3: Find Out How Many Bags of Concrete Do I Need

  • To find the bags required to pour the slab, we need to divide the volume of concrete by yield of concrete bags.
  • Bags are generally available in different sizes like 40lb, 45lb, 60lb, 80lb, and 90lb.

Different bag sizes and their yield values are given in the chart-

Sizes of bag

Yield
40 lb (18.1 kg) 0.3 cubic feet (0.008 cubic meter)
45 lb (20.4 kg) 0.34 cubic feet (0.01 cubic meter)
60 lb (27.2 kg) 0.45 cubic feet (0.012 cubic meter)
80 lb (36.2 kg) 0.6 cubic feet (0.016 cubic meter)
90 lb (40.8 kg) 0.68 cubic feet (0.02 cubic meter)
  • From the upper table, we are using a 40 lb bag and the yield value is 0.011 cubic yards.
  • So, number of bags are calculated by dividing total volume of concrete with yield vale of bags.
  • So, 1.35/0.011 = 122 bags
  • So, for 10 x 10 slab with a thickness of 4”, we need 122 bags of concrete.

Also, read: What Is Unit Weight | What Is Density | What Is Unit Weight Material | Unit Weight Building Materials

Useful Article For You

Different Brands of Dry Mix Concrete Bags

Different Brands of Dry Mix Concrete Bags

Different brands of dry mix concrete bags are-

  • Ultra Tech Cement
  • ACC Limited
  • Nuvoco
  • RDC Concrete
  • Build Supply
  • Shaila

Also, read: What Is Plumbing | Systems of Plumbing | Difference Between One pipe, Two Pipe, Single Stack, and Single Stack Partially Ventilated | How to Choose of Plumbing System.

How Many Bags of Concrete Do I Need for Slab with 4” Thickness?

Method – 1 

  • The weight of dry concrete is 3600 pounds per cubic yard.
  • So, the weight of dry concrete per cubic foot = 3600/ = 133.34 pounds
  • [as we know, 1 yard = 3 feet]

Let’s Assume,

  • Length of slab = 5 feet
  • Width of slab = 5 feet
  • S0, the weight of dry concrete = [{Length (in foot) x Width (in foot) x Thickness (in inches) / 12} x 133.34] = Weight (in pounds)

In this Case,

  • [(5 x 5 x 4) / 12] x 133.34 = 1111.16 pounds = 504 kg
  • The weight of one of dry cement concrete is 40 kg
  • So, the number of bags are required = 504/40 = 12.6 nos.

Method – 2

Step-1: Calculate Volume of Concrete Required Pouring 5 X 5 Slab Thickness 4 inch

The calculation of volume of slab is the multiplying of length, width, and thickness.

Example: 

Let’s consider 5×5 slab with thickness 4”

  • Length= 5 feet
  • Width= 5 feet
  • Thickness= 4”
  • Volume of concrete= L x B x T
  • Volume of concrete = 5 x 5 x (0.33)
  • Volume of concrete = 8.25 cu. Ft. …………(Because 12” = 1 feet, 4/12 = 0.33 feet)
  • It is equal to 0.23 cu. Meter or 0.3 cubic yard.

Explanation:

  • 3 ft= 1 yard, 3ft x 3 ft x 3ft = 1 yard x 1 yard x 1 yard
  • 27 cubic feet = 1 cubic yard
  • After that we divide 8.25 cubic feet by 27 to get the volume of concrete in cubic yard.
  • Volume of concrete = 8.25/27 = 0.3 cubic yard

Step-2: Adding 10% of Extra Volume

  • Now we are adding 10% of extra volume because of dry volume and wastage of concrete.
  • 0.3 x 10% = 0.3 x (10/100) = 0.03 cubic yard
  • So, the total volume of concrete = Original volume + Extra volume = 0.3 + 0.03 = 0.33 cubic yard

Step-3: Find Out How Many Bags of Concrete Do I Need

  • To find the bags required to pour the slab, we need to divide the volume of concrete by yield of concrete bags.
  • Bags are generally available in different sizes like 40lb, 45lb, 60lb, 80lb and 90lb.

Different bag sizes and their yield values are given in the chart-

Sizes of bag

Yield
40 lb (18.1 kg)

0.3 cubic feet (0.008 cubic meter)
45 lb (20.4 kg)

0.34 cubic feet (0.01 cubic meter)
60 lb (27.2 kg)

0.45 cubic feet (0.012 cubic meter)
80 lb (36.2 kg)

0.6 cubic feet (0.016 cubic meter)
90 lb (40.8 kg)

0.68 cubic feet (0.02 cubic meter)
  • From the upper table, we are using 40 lb bag and the yield value is 0.011 cubic yard.
  • So, number of bags are calculated by dividing total volume of concrete with yield vale of bags.
  • So, 0.33/0.011 = 30 bags
  • So, for 5 x 5 slab with a thickness of 4”, we need 30 bags of concrete.

How Many Bags of Concrete Do I Need for Slab with 5” Thickness?

Method – 1 

Let’s assume,

  • Length of slab = 5 feet
  • Width of slab = 5 feet
  • Previously we determined that the weight of dry concrete per cubic foot is 133.34 pounds.
  • S0, the weight of dry concrete = [{Length (in foot) x Width (in foot) x Thickness (in inches) / 12} x 133.34] = Weight (in pounds)

In this case,

  • [(5 x 5 x 5) / 12] x 133.34 = 1389 pound = 630 kg
  • The weight of one of dry cement concrete is 40 kg
  • So, the number of bags are required = 630/40 = 16 nos.

Method – 2

Step-1: Calculate Volume of Concrete Required Pouring 5 X 5 Slab Thickness 5 inch

The calculation of volume of slab is the multiplying of length, width and thickness.

Example:

  • Let’s consider 5×5 slab with thickness 5”
  • Length= 5 feet
  • Width= 5 feet
  • Thickness= 5”
  • Volume of concrete= L x B x T
  • Volume of concrete = 5 x 5 x (0.42)
  • Volume of concrete = 10.5 cu. Ft………..(Because 12” = 1 feet, 5/12 = 0.42 feet)
  • It is equal to 0.39 cubic yard.

Explanation:

  • 3 ft= 1 yard, 3ft x 3 ft x 3ft = 1 yard x 1 yard x 1 yard
  • 27 cubic feet = 1 cubic yard
  • After that we divide 10.5 cubic feet by 27 to get the volume of concrete in cubic yard.
  • Volume of concrete = 10.5/27 = 0.39 cubic yard

Step-2: Adding 10% of Extra Colume

  • Now we are adding 10% of extra volume because of dry volume and wastage of concrete.
  • 0.39 x 10% = 0.39 x (10/100) = 0.04 cubic yard
  • So, the total volume of concrete = Original volume + Extra volume = 0.3 + 0.04 = 0.34 cubic yard

Step-3: Find Out How Many Bags of Concrete Do I Need

  • To find the bags required to pour the slab, we need to divide the volume of concrete by yield of concrete bags.
  • Bags are generally available in different sizes like 40lb, 45lb, 60lb, 80lb, and 90lb.

Different bag sizes and their yield values are given in the chart-

Sizes of bag

Yield
40 lb (18.1 kg)

0.3 cubic feet (0.008 cubic meter)
45 lb (20.4 kg)

0.34 cubic feet (0.01 cubic meter)
60 lb (27.2 kg)

0.45 cubic feet (0.012 cubic meter)
80 lb (36.2 kg)

0.6 cubic feet (0.016 cubic meter)
90 lb (40.8 kg)

0.68 cubic feet (0.02 cubic meter)
  • From the upper table, we are using 40 lb bag and the yield value is 0.011 cubic yard.
  • So, a number of bags are calculated by dividing total volume of concrete with yield vale of bags.
  • So, 0.34/0.011 = 30.9 bags = 31 bags
  • So, for 5 x 5 slab with a thickness of 5”, we need 31 bags of concrete.

Also, read: What Is Self Compact Concrete | What Is J-ring Test | Equipment of J-ring Test | Procedure of the J-Ring Test

How Many Bags of Concrete Do I Need for Slab with 6” Thickness?

Method – 1 

Let’s assume,

  • Length of slab = 5 feet
  • Width of slab = 5 feet
  • Previously we determined that the weight of dry concrete per cubic foot is 133.34 pounds.
  • S0, the weight of dry concrete = [{Length (in foot) x Width (in foot) x Thickness (in inches) / 12} x 133.34] = Weight (in pounds)

In this case,

  • [(5 x 5 x 6) / 12] x 133.34 = 1666.75 pounds = 756 kg
  • The weight of one of dry cement concrete is 40 kg
  • So, the number of bags are required = 756/40 = 19 nos.

Method – 2

Step-1: Calculate Volume of Concrete Required Pouring 5 X 5 Slab Thickness 6 inch

The calculation of volume of slab is the multiplying of length, width and thickness.

Example: 

  • Let’s consider 5 x 5 slab with thickness 6”
  • Length= 5 feet
  • Width= 5 feet
  • Thickness= 6”
  • Volume of concrete= L x B x T
  • Volume of concrete = 5 x 5 x (0.5)
  • Volume of concrete = 12.5 cu. Ft…………(Because 12” = 1 feet, 6/12 = 0.5 feet)
  • It is equal to 0.46 cubic yard.

Explanation:

  • 3 ft= 1 yard, 3ft x 3 ft x 3ft = 1 yard x 1 yard x 1 yard
  • 27 cubic feet = 1 cubic yard
  • After that, we divide 12.5 cubic feet by 27 to get the volume of concrete in cubic yard.
  • Volume of concrete = 12.5/27 = 0.46 cubic yard

Step-2: Adding 10% of Extra Volume

  • Now we are adding 10% of extra volume because of dry volume and wastage of concrete.
  • 0.46 x 10% = 0.46 x (10/100) = 0.05 cubic yard
  • So, the total volume of concrete = Original volume + Extra volume = 0.3 + 0.05 = 0.35 cubic yard

Step-3: Find Out How Many Bags of Concrete Do I Need

  • To find the bags required to pour the slab, we need to divide the volume of concrete by yield of concrete bags.
  • Bags are generally available in different sizes like 40lb, 45lb, 60lb, 80lb, and 90lb.

Different bag sizes and their yield values are given in the chart-

Sizes of bag

Yield
40 lb (18.1 kg)

0.3 cubic feet (0.008 cubic meter)
45 lb (20.4 kg)

0.34 cubic feet (0.01 cubic meter)
60 lb (27.2 kg)

0.45 cubic feet (0.012 cubic meter)
80 lb (36.2 kg)

0.6 cubic feet (0.016 cubic meter)
90 lb (40.8 kg)

0.68 cubic feet (0.02 cubic meter)
  • From the upper table, we are using 40 lb bag and the yield value is 0.011 cubic yard.
  • So, a number of bags are calculated by dividing total volume of concrete with yield vale of bags.
  • So, 0.35/0.011 = 31.8 bags = 32 bags
  • So, for 5  x 5 slabs with a thickness of 6”, we need 32 bags of concrete.

Useful Article for You

How Many Bags of Concrete Do I Need for Slab with 8” Thickness?

Method – 1 

Let’s assume,

  • length of slab = 5 feet
  • width of slab = 5 feet
  • Previously we determined that the weight of dry concrete per cubic foot is 133.34 pounds.
  • S0, the weight of dry concrete = [{Length (in foot) x Width (in foot) x Thickness (in inches) / 12} x 133.34] = Weight (in pounds)

In this case,

  • [(5 x 5 x 8) / 12] x 133.34 = 2223 pound = 1008.34 kg
  • The weight of one of dry cement concrete is 40 kg
  • So, the number of bags are required = 1008.34/40 = 25 nos.

Method – 2

Step-1: Calculate Volume of Concrete Required Pouring 5 X 5 Slab Thickness 7 inch

The calculation of volume of slab is the multiplying of length, width and thickness.

Example:

  • Let’s consider 5×5 slab with thickness 8”
  • Length= 5 feet
  • Width= 5 feet
  • Thickness= 8”
  • Volume of concrete= L x B x T
  • Volume of concrete = 5 x 5 x (0.67)
  • Volume of concrete = 16.75 cu. Ft…………… (Because 12” = 1 feet, 8/12 = 0.67 feet)
  • It is equal to 0.62 cubic yard.
  • Explanation:
  • 3 ft= 1 yard, 3ft x 3 ft x 3ft = 1 yard x 1 yard x 1 yard
  • 27 cubic feet = 1 cubic yard
  • After that we divide 16.75 cubic feet by 27 to get the volume of concrete in cubic yard.
  • Volume of concrete = 16.75/27 = 0.62 cubic yard

Step-2: Adding 10% of Extra Volume

  • Now we are adding 10% of extra volume because of dry volume and wastage of concrete.
  • 0.62 x 10% = 0.62 x (10/100) = 0.062 cubic yard
  • So, the total volume of concrete = Original volume + Extra volume = 0.3 + 0.062 = 0.362 cubic yard

Step-3: Find Out How Many Bags of Concrete Do I Need

  • To find the bags required to pour the slab, we need to divide the volume of concrete by yield of concrete bags.
  • Bags are generally available in different sizes like 40lb, 45lb, 60lb, 80lb, and 90lb.

Different bag sizes and their yield values are given in the chart-

Sizes of bag

Yield
40 lb (18.1 kg)

0.3 cubic feet (0.008 cubic meter)
45 lb (20.4 kg)

0.34 cubic feet (0.01 cubic meter)
60 lb (27.2 kg)

0.45 cubic feet (0.012 cubic meter)
80 lb (36.2 kg)

0.6 cubic feet (0.016 cubic meter)
90 lb (40.8 kg)

0.68 cubic feet (0.02 cubic meter)
  • From the upper table, we are using a 40 lb bag and the yield value is 0.011 cubic yards.
  • So, a number of bags are calculated by dividing total volume of concrete with yield vale of bags.
  • So, 0.362/0.011 = 32.9 bags = 33 bags
  • So, for 5  x 5 slab with a thickness of 8”, we need 33 bags of concrete.

Also, read: What Is Self Compact Concrete | What Is Slump Flow Test | Equipment for Slump Flow Test | Procedure of Slump Flow Test

How Many Bags of Quikrete Do I Need?

How Many Bags of Quikrete Do I Need?

There are different numbers of bags are required a certain square feet design. The number of bags depends on the weight of those bags.

So, first, let’s assume the dimension of the required area is (5 x 5)= 25 square feet.

Quikrete bags required for-

Different weights for a 5 ‘x 5’ x 4 “slab size in a hair bag are as follows.

Weight of one bag

 40 lb. 50 lb. 60 lb. 80 lb.

No. Of bags required

 28 23 19 14

Different weights for a 5 ‘x 5’ x 5″slab size in a hair bag are as follows.

Weight of one bag

 40 lb. 50 lb. 60 lb. 80 lb.

No. Of bags required

 35 28.5 23.5 17.5

Different weights for a 5 ‘x 5’ x 6″slab size in a hair bag are as follows.

Weight of one bag

 40 lb. 50 lb. 60 lb. 80 lb.

No. Of bags required

 42 34 28 21

Different weights for a 5 ‘x 5’ x 8″slab size in a hair bag are as follows.

Weight of one bag

 40 lb. 50 lb. 60 lb. 80 lb.

No. Of bags required

 56 45 37 28

Also, read: What Is Self Compact Concrete | What Is Slump Flow Test | Equipment for Slump Flow Test | Procedure of Slump Flow Test

How Much Concrete Do I Need?

How Much Concrete Do I Need?

  • According to the requirements of concrete, the bags will be decided.
  • If the structure is large then it requires more bags of concrete and if the structure is small compared to the large structure then it required less number of bags.
  • The example of how many bags of concrete do I need for a 10’ x 10’ x 5” slab is below-
  • The weight of concrete= [(10 x 10 x 5)/12] x 133.34 = 5556 pound
  • We know the density of dry mix concrete is 133 lb
  • So, the volume is (5556/133)  = 41.78  = 1.18
  • So, we need to order 1.18  dry concrete.
FAQ

Bags of Concrete

Boral makes no guarantee of the accuracy or completeness of the information and recommends you conduct your own testing to determine suitability for your specific purpose. One 20kg bag will cover an area of 1.1m2 to a depth of approximately 10mm. Or 108 x 20kg bags equates to one cubic meter of mixed concrete.

Quikrete Super Sacks

One 50-pound bag of quikrete fast-setting concrete mix yields about. 375 cubic feet. For example, if you need to cover 33.333 cubic feet, using 60-pound bags of concrete, divide 33.333 cubic feet by. 45 cubic feet to get 74.07 total bags of concrete.

Mixed Cement Bags

General description: “acc baguette” is a carefully proportioned blend of high-quality raw materials including well-graded fine & coarse aggregates, ordinary portland cement, and special concrete admixtures. Uses individual houses, gardens, small concrete repair works, small structures – foundations, columns, slabs, etc.

Lightweight Concrete Bag Mix

Using less sand can make the product lighter, but it can also make the concrete weaker structurally. A simple recipe for basic lightweight concrete is to combine 8 parts sand, 8 parts cement and 8 parts perlite to 5 parts water.

Concrete Mix Ready to Use

Ready-mix concrete tends to be better for many projects, in spite of its higher cost. Ready-mix concrete offers a higher quality, and variation between batches is minimal when concrete is prepared in a plant environment.

Quikrete Rip Rap

Rip rap is a loose stone used as a foundation for a breakwater. It is also used as a form of erosion control and can be seen on large embankments, shorelines, creeks, rivers and around discharge pipes.  Dense broken concrete, stone blocks and other durable material shaped into cubic form make up SCC’s product.

80 lb Quikrete Concrete Mix

15 cubic feet for every 20 pounds of a mix, so a 40-pound bag yields. 30 cubic feet, 60 pounds of concrete mix yields . 45 cubic feet and an 80-pound bag yields. 60 cubic feet.

Concrete Grout Bags

You can use a mixture of cement, sand, and water within a grout bag to repair the brick structure. The grout bag works like a pastry bag to apply a controlled layer of cement mixture.

Small Bag Concrete Mix

The recommended water amount for each eighty-pound bag of concrete mix will require about three quarts of water for approximately two-thirds of the water into the depression.

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