Concrete and cement – are they the same thing? The answer may surprise you.
Known for their strength and durability, concrete and cement are two of the most popular materials used in construction. But what is the difference between the two – if any?
Is Concrete the Same as Cement?
No. Concrete and cement are often used interchangeably, but they are two different things. Cement is merely a component of concrete.
Portland cement is typically used to create concrete. It’s mixed with water to create a paste, which then surrounds sand and stone, binding the materials together to create an ultra-hard surface. The chemical reaction caused by mixing these ingredients causes the paste to harden and strengthen.
Cement vs Concrete
If cement and concrete aren’t the same thing, then what is the difference between the two? What are their uses?
What is Cement?
Cement is a binder that’s used to stick building materials together. It consists of calcium, clay, limestone and other silica-rich materials. Cement may also contain iron ore, bauxite, chalk, shells, shale, marl, slate and slag.
All of these ingredients are mixed together and heated to around 2,700 degrees Fahrenheit to create a solid substance called clinker. Clinker is then ground into powder form and can be mixed with water to create a paste.
Cement has excellent adhesive and binding properties, but on its own, it’s susceptible to cracking.
The most common type of cement used in construction is Portland cement. There are five main types of Portland cement. The majority of Portland cement sold in North America is Type I, which has moderate sulfate resistance.
What Do You Use Cement For?
Cement can be used for smaller projects, like grouting and certain types of masonry projects. It can also be used to fix crumbling or cracked concrete.
In addition to concrete, cement is also a component of other building material components, including:
Mortar
Cement is also be used to create mortar. Mortar consists of lime, cement and fine sand. The cement acts as the binding agent to hold bricks, stone and blocks together.
Stucco
Stucco is used to finish building exteriors. It’s typically applied over brick or stone to create a long-lasting, breathable surface that’s easy to maintain.
Stucco consists of cement, plasticizers, sand, pigments and waterproofing agents.
What is Concrete?
Concrete actually contains cement. Cement is mixed with water to create a paste and then combined with gravel and sand to create concrete.
Concrete consists of four main ingredients:
- Cement: Used as a binding agent to hold all of the materials together. Typically, cement accounts for 10-15% of the concrete mix.
- Water: The most important ingredient in concrete. Water is used for hydration to initiate the chemical reaction that hardens the mixture, and it’s also used to make the mixture workable.
- Aggregates: Course and fine aggregates, including sand, crushed stone and gravel.
- Admixtures: Additional ingredients, such as accelerators, chemical retardants, superplasticizers, water reducers and more.
Concrete is one of the strongest and most durable materials on the planet. It’s used to build bridges, sidewalks, dams and structures, but it can also be used in small, DIY projects, like kitchen countertops and landscape hardscapes.
There are several types of concrete, including:
- Self-consolidating
- Polymer
- Pervious
- Shotcrete
- High-performance
To achieve the durability and strength that concrete is known for, the ingredients must be carefully mixed and proportioned. Too little cement will result in porous concrete, while too much cement can result in cracking and be costly to repair. The goal is to use as little water as possible in the mix without compromising the workability of the mixture. Less water leads to a higher-quality concrete when properly placed and cured.
Concrete continues to harden for years, which means it only gets stronger as time goes on. The type of cement that’s used to create concrete will determine how long it takes to set and its strength.
Concrete can be purchased in premixed bags and mixed on-site, or it can be brought already pre-mixed by truck and ready to pour.
The Takeaway
Concrete and cement are not the same thing.
Cement is a component of concrete. Concrete is the complete building material and one of the strongest building materials available. It consists of a variety of ingredients designed to form a hard, ultra-durable surface that will last for decades to come.
