What is the density of concrete?

The article aims to answer the question “what is the density of concrete?”. It will also highlight the method you can estimate the required weight of concrete to make slabs. The article will also discuss the benefits and problems associated with lightweight and fly ash concrete.

What is the density of concrete?

Density per cubic foot (lb/ft3) for regular concrete is 150, whereas that for lightweight concrete is 110 pcf/lb/ft3/m3.

The mass or weight of concrete needed to fill a container of a specific capacity is known as the bulk density or unit weight of concrete.

Concrete is a composite material made by combining binding material (cement or lime) with aggregate (sand, gravel, stone, brick chips, etc.), water, admixtures, and other substances in precise quantities. There are a number of variables that might affect the strength and quality of the finished product.

How can I figure out the density of concrete?

If you want to figure out the density of concrete, the quickest and most precise method is to weigh a known amount of concrete. It is a mass to volume ratio that determines the density of an object. Concrete’s sturdiness may be gauged by looking at its density. 

Higher and lower densities may be achieved by altering the mixing procedure. Steel wires stretched by hydraulic jacks create a high-density concrete mix. It takes a few minutes for the concrete to set before the jacks can be released. 

Concrete is compressed as the wires tighten. Bridges, roofs, and floors may all be built using compressed concrete. When it comes to adverse weather conditions, air-enhanced concrete performs well and is employed in highways and runways. Pumice, a mineral that is very light in weight, is used as an aggregate in lightweight concrete.

A simple method for figuring out concrete’s density is to start by figuring out the density of the constituent elements. The weight of one cubic meter of cement varies from 830 kilograms to 1,650 kilograms, or 52 pounds to 103 pounds. 

More thick cement, such as that carried by truck, has been stored and subjected to vibration after being pneumatically put into cement silos. As a general rule of thumb, one cubic foot of newly packed 94-pound bags of cement equals one metric ton. 

During transit, it will spontaneously decompress. It is obvious that cement should be measured in mass rather than volume because of its huge bulk volume. Concrete’s density is around 2,400 kg per cubic meter, or 145 pounds per cubic foot, for concrete of average weight. 

How much aggregate, how much air is entrained, the cement concentration, and the maximum aggregate size are all factors that affect concrete density. At 115 pounds per square foot, lightweight concrete is the lightest in the industry.

How much does concrete weigh?

The amount of air and water it contains may affect the weight of concrete. The importance of cement may range from 830 to 1650 kilograms per cubic meter, equivalent to 52 to 103 pounds per cubic foot.

Denser cement is obtained by storing and transporting cement subjected to vibration, as opposed to glue placed into silos pneumatically. Consider that a 94 lb. a bag of newly packed cement equals one cubic foot when weighed.

Lightweight concrete density is 1920 kg per cubic meter (116 lbs per cubic foot) or 116 kilograms per cubic meter (3132 lbs per cubic yard). It weighs less because it is created of pumice, an inherently light mineral.

It is a mass to volume ratio that determines density. The simplest and most accurate method for determining the density of concrete is to fill a specified volume container and weigh it.

Checking concrete strength using test cylinders benefits knowing, comprehending, and monitoring density. In most cases, a decrease in concrete density results in a reduction of concrete strength.

These strength tests may be performed every 24 hours, seven days, and 28 days in a laboratory to detect potential weakness (or lower density). This is critical because concrete is utilized in so many high-strength structures (bridges and high-rises).

In the case of concrete countertops or inside radiant floor heating, you may question whether utilizing lightweight concrete will reduce stress on cabinets and flooring below.

It weighs roughly 18 pounds per square foot for conventional weight concrete and about 14.5 lbs per square foot for lightweight concrete.

Even though concrete countertops weigh less than regular concrete, it’s still simpler to polish standard density concrete because of the 3.5 pounds per square foot weight savings.

Using a vast concrete area for flooring might save a significant amount of weight. Keep in mind that the cost of lightweight concrete is generally twice as much as that of ordinary concrete.

How can I calculate the weight of a square foot of concrete?

You may use the following formula to get its weight in pounds per square foot if you know how thick your concrete is.


Take the thickness of your concrete and divide it by 12. (this gives you the depth in feet.)

As an illustration: Dividing six by twelve gives you five percent (a 6-inch slab is .5 feet thick)

One hundred forty-five pounds per cubic foot x.5 = 72.5 pounds per cubic foot or 72.5 pounds per cubic meter.

A 6-inch thick slab weighs 72.5 pounds per square foot, the maximum allowable weight.

Do you know the weight of a 4-inch-thick slab of concrete?

The weight per square foot is 47.85 pounds when divided by the number of decimal places in the formula (4/12).

What is the weight of structural lightweight concrete?

For comparison, ordinary concrete weighs 150 pounds per cubic foot, whereas lightweight structural concrete weighs around 105 pounds per cubic foot. 

It is possible to reduce the density of lightweight concrete by using a lesser quantity of light coarse particles and light fine aggregates.

Expanded clay, clay, or slate materials turned into a porous structure mimicking volcanic rock are often used in lightweight aggregate materials. Certain mixtures of slag from air-cooled blast furnaces may also be used.

Structures may benefit from smaller columns, footings, and other components that carry the weight of the building’s contents because of this.

In terms of compressive strength, lightweight structural concrete may be built to be as strong as normal-weight concrete. The mechanical and physical qualities of regular-weight concrete are identical to those of lightweight concrete.

In most projects, the higher cost of lightweight concrete is offset by fewer structural components, less reinforcing steel, and a smaller volume of concrete.

This will result in a more fire-resistant structure when using lightweight concrete. It provides wall components with higher R-values for improved insulation. It all comes down to these two variables when it comes to lightweight concrete as a construction material.

The aggregates must be wetted before use to obtain a high degree of saturation. This may happen if the mix isn’t entirely saturated with aggregates.

An airtight seal encases the bulk of lightweight concrete. The air content must be monitored and maintained to ensure that density requirements are satisfied.

Polishing lightweight concrete requires a higher degree of caution. The light stones will separate from the mortar if the slump is too severe or too much water present. Avoid blisters and delaminations on hand-trodden interior flooring.

When it comes to the drying time of lightweight concrete, it tends to be longer than that of ordinary concrete. While painting the last coat, keep this in mind.

In concrete and steel buildings like parking structures, tilt-up walls, composite slabs on metal decking and piers and beams, lightweight structural concrete has been used to make bridge decks and other structural components (SLC).

If you have a wood-framed deck, a quantity of lightweight concrete may be used to restrict the warm air from escaping.

When dealing with lightweight concrete, pumping the material may be a challenge. A sound pump installation may be achieved by taking certain precautions ahead of time.

What are the properties of concrete?

·   Cement and concrete are often used interchangeably by the general public. The word “concrete” refers to a composite of three concrete qualities, and glue is just one of them.

·   Water, aggregate (rocks and sand), and portland cement are the three main concrete components. When water and aggregates are combined with powdered cement, it forms a strong bond.

·   We’re all aware of concrete, a long-lasting building material made from a combination or mixture.

·   It’s a simple blend to put together and put back together.

·   Use the lowest feasible water-cement ratio, the correct size coarse aggregate for your task, and the optimal ratio of fine to coarse aggregate to achieve excellent quality concrete.

·   For the freezing and thawing resistance, deicing chemical resistance, wear resistance, strength, and low permeability of hardened concrete (water tightness).

·   To make a concrete mix, you need to know the fundamentals of definite characteristics. Admixtures that enhance workability, durability and set times are also used. 


Several variables affect the density of concrete, including the quantity of water and air in the mix. To put it another way, a block of concrete that is one foot wide, one foot long, and one foot high would typically weigh 150 pounds when measured in pounds per cubic foot (lb/ft3).

Assuming that a cubic foot of concrete weighs 2400 kilograms per cubic foot, a block of concrete that is one meter wide, one-meter long, and 1-meter high would weigh 2400 kilograms.

Frequently asked questions (FAQS):What is the density of concrete?

What is the density of concrete?

Density per cubic foot (lb/ft3) for regular concrete is 150, whereas that for lightweight concrete is 110 pcf/lb/ft3/m3.

The mass or weight of concrete needed to fill a container of a specific capacity is known as the bulk density or unit weight of concrete.

When cured, does concrete get heavier?

As the cement hardens, the quantity of water that interacted with the cement is reflected in the cement’s weight difference from when it was fresh. A bag of hardened cement will always be heavier than a fresh bag because of this.

Concrete or sand is heavier?

Almost usually, water at its densest is used as a benchmark for liquids! In comparison, the density of sand ranges from 2.65 to 2.67. Cement is heavier than sand in terms of scientific weight!


El-Dieb, A. S. (2007). Self-curing concrete: Water retention, hydration and moisture transport. Construction and Building Materials, 21(6), 1282-1287.

Sakr, K., & El-Hakim, E. (2005). Effect of high temperature or fire on heavy weight concrete properties. Cement and concrete research, 35(3), 590-596.

What was missing from this post which could have made it better?

Leave a Comment