How many cubic feet is a 90 pound bag of Portland cement?

Portland cement is a vital construction material used to make concrete, mortars, stuccos and grouts. It is commonly packaged and sold in 94 pound bags, which contain 1 cubic foot of cement. However, sometimes Portland cement is sold in 90 pound bags instead. Determining the cubic feet in a 90 pound bag requires some simple calculations.

Key Points

  • Portland cement is commonly packaged and sold in 94 pound bags containing 1 cubic foot of cement.
  • Some brands sell Portland cement in 90 pound bags instead of 94 pounds.
  • To calculate the cubic feet in a 90 pound bag, divide the weight by the density of Portland cement.
  • With a density around 100 pounds per cubic foot, a 90 pound bag contains around 0.9 cubic feet of cement.

Typical Packaging of Portland Cement

Portland cement is a standard construction material used to create concrete and mortars. It is commonly packaged and sold in 94 pound paper bags, which each contain 1 cubic foot of loose cement powder. The 94 pound weight per bag makes calculations and measurements straightforward for construction projects. Each bag provides exactly 1 cubic foot of cement material.

Most major brands of Portland cement like Quikrete, Sakrete and Lehigh package their standard cement products in 94 pound bags containing 1 cubic foot. This consistent and standard bag size has been used for decades in the construction industry. It provides a convenient container to handle the loose cement powder efficiently at construction sites. The 94 pound weight corresponds to the density of Portland cement, which is around 94-100 pounds per cubic foot.

Why 90 Pound Bags Are Sometimes Used

While 94 pounds per bag is the common standard for Portland cement, some specialty products use 90 pound bags instead. The slightly smaller 90 pound size reduces weight for certain applications. The most common uses for 90 pound cement bags include:

  • White Portland cement: White cement weighs slightly less than standard gray cement, allowing for 90 pound bags.
  • Masonry cement: Masonry cement has lighter additives, so 90 pound bags are sometimes used.
  • Repair products: Some concrete repair products have additives that reduce weight.
  • High volume retailers: Big box stores may use 90 pound bags to reduce labor for stocking shelves.

While still less common than 94 pound bags, the 90 pound size is used for specific Portland cement products where reducing weight provides some benefits. But it still provides the convenience of a standard sized bag for handling the cement powder efficiently.

Density of Portland Cement

To determine how many cubic feet are in a 90 pound bag of cement, you need to know the density of Portland cement. Density is measured by pounds per cubic foot (lb/ft3). It represents how much a given volume of a material weighs. Standard Portland cement has a density of around 94-100 lb/ft3 depending on its exact composition.

Here are some approximate density values for different types of Portland cement:

Cement Type Density (lb/ft3)
General purpose Portland cement 94-100
White Portland cement 90-98
Masonry cement 90-94
Rapid hardening cement 95-100

As the table shows, standard gray Portland cement has a density right around 100 lb/ft3. White cement and masonry cement are slightly less dense in the 90-98 lb/ft3 range. But all types of Portland cement are going to be reasonably close to 100 lb/ft3 density.

Calculating Cubic Feet in a 90 Pound Bag

With the density of Portland cement around 100 lb/ft3, we can now calculate how many cubic feet are in a 90 pound bag:

Cubic feet = Weight (pounds) / Density (pounds per cubic foot)

For a 90 pound bag:

Cubic feet = 90 lb / 100 lb/ft3 = 0.9 ft3

So for Portland cement with a density of 100 lb/ft3, a 90 pound bag will contain 0.9 cubic feet of cement.

If we assume a lower density of 94 lb/ft3 for masonry cement, then the calculation would be:

Cubic feet = 90 lb / 94 lb/ft3 = 0.96 ft3

So a 90 pound bag of the lighter masonry cement will contain around 0.96 cubic feet. But for standard Portland cement, 0.9 cubic feet is the approximate volume you’ll get in a 90 pound bag.

Example Volume Calculations

To visualize the volume in cubic feet provided by a 90 pound cement bag, you can calculate the dimensions of that 0.9 cubic foot volume. For example:

  • 0.9 cubic feet could be a 9 inch x 9 inch x 12 inch volume
  • Or it could be a 6 inch x 15 inch x 12 inch volume
  • It could also be a 18 inch x 18 inch x 6 inch volume

Cubic feet is just the three dimensional volume, so it can take any cube or rectangular shape. But knowing you get around 0.9 cubic feet helps estimate how much cement a 90 pound bag will provide for your project needs.

Weight to Volume Conversions

For quick reference, here are some handy conversions between weight and volume for Portland cement:

  • 1 cubic foot = 94-100 pounds
  • 94 pound bag = 1 cubic foot
  • 90 pound bag = 0.9-0.96 cubic feet
  • 1 pound = 0.01 cubic foot

You can use these conversions to easily calculate volume when you know the weight in pounds. Or to estimate weight if you know the volume in cubic feet.

Weights for Full Pallet Quantities

When purchasing Portland cement in bulk, it is often packaged on pallets for transport and delivery. Here are some example full pallet weights:

Pallet Bags Weight
Half pallet 24 bags 2,160 pounds (24 x 90 lb)
Full pallet 48 bags 4,320 pounds (48 x 90 lb)

As you can see, a half pallet holds 24 bags totaling 2,160 pounds. A full pallet holds 48 bags totaling 4,320 pounds of cement. With 90 pound bags, the total weight on pallets increments by 90 pounds per bag added.

Volume Amounts for Projects

When planning a DIY project, it’s important to estimate the volume of cement required. Here are some example project volumes:

  • 4×8 foot patio = 0.9 cubic yards of cement
  • Post hole (12″ diameter x 24″ deep) = 0.66 cubic feet of cement
  • 100 linear feet of sidewalk (4 feet wide x 4 inches thick) = 4.4 cubic yards of cement
  • Cubic yard of fresh concrete = 2,900 pounds of cement

These examples demonstrate how cubic feet, cubic yards and pounds are all important units when estimating concrete and cement needs for projects. Planning with the correct volumes and weights ensures you purchase the right quantities.

Cost Factors

When budgeting for cement, some cost factors to note based on weight include:

  • 90 pound bags range $8 – $12 per bag
  • Bulk prices range $100 – $160 per ton
  • Delivery fees for bulk orders average $100 per truckload

Always call suppliers to get current pricing for your area. Buying in bulk usually offers the biggest cost savings on cement.

Conclusion

In summary, a 90 pound bag of Portland cement contains around 0.9 cubic feet of volume. This is slightly less than the standard 1 cubic foot provided in a 94 pound bag. Using the density of Portland cement, you can calculate the cubic feet of cement based on a known weight. This allows proper estimating of bag quantities for any construction or concrete project using Portland cement. Careful calculations of volumes and weights ensures you get the right amount of cement mix for your particular DIY, concrete, construction and home improvement projects.

1 thought on “How many cubic feet is a 90 pound bag of Portland cement?”

  1. Your specs for calculating volume are somewhat misleading. You say a 90 lb. bag of cement is equal to 5.889 cu. ft. Actually a 90 lb. bag holds .94 cu. ft. of cement, and has a YIELD of 5.889 cu. ft. of concrete when mixed 1:5 with aggregate. A 94 lb. bag holds 1 cu. ft. of cement, and has a YIELD of 6 cu. ft. when mixed with 5 cu. ft. of aggregate. What do you mean by “is equal to?”
    You say, “Generally, it takes about 6-8 pounds of cement for one yard of concrete.” A cu. yard of aggregate weights apporoximately 2500 lbs. so a 1:5 mix would require 500 lbs. of cement, assuming the cement and aggregate have similar densities.

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