Cement and concrete are terms often used interchangeably, but you can’t swap one out for the other in construction projects. They’re two distinct substances with different properties and uses—cement is actually an ingredient in concrete. This guide discusses concrete vs. cement, their various applications, and how to effectively work with these materials.
What Is Cement?
Cement is composed of calcium oxide (lime), silicon dioxide (silica), aluminum oxide (alumina), iron, and gypsum. Manufacturers burn materials, such as shells, blast furnace slag, and limestone, in a kiln and then pulverize the remains to create the fine powder known as cement.
Powdered cement and water create a paste that hardens over time. It’s a binding agent that holds sand, gravel, crushed rock, and other ingredients together. Cement is rarely used on its own, but it’s a key ingredient in concrete and mortar.
Portland cement is the most common type used in building materials. According to the Portland Cement Association (PCA), concrete mix contains up to 15% cement.
What Is Concrete?
Concrete is a versatile, durable, and easy to source building material best for various construction and home improvement projects. It’s a blend of cement, aggregates (such as sand, gravel, or crushed stone), air, and water. Water and cement react to activate cement’s binding properties. After the mixture sets, hardens, and cures, it turns to concrete.
Concrete offers several advantages that make it a popular choice for construction projects around the world:
- Versatility: Concrete comes in many types, strengths, weights, and setting times, allowing more customization for specific applications and conditions.
- Moldability: When wet, you can pour concrete into forms and mold it to create various structures, from slabs and foundations to sidewalks and decorative planters.
- Strength: Concrete boasts excellent compressive strength, making it well-suited for load-bearing applications and structural elements.
- Cost-effectiveness: It’s generally a budget-friendly option, providing durability and longevity with a relatively low investment.
How To Work With Concrete
Whether you’re tackling a DIY project or overseeing professional work, here are some key tips for successful concrete projects:
Mixing Concrete
The quality of the final concrete product depends significantly on proper mixing techniques. Work with clean tools and forms to avoid contamination. Always wear protective gear, such as gloves and safety glasses, to prevent skin irritation and eye injuries. Mix the concrete thoroughly until it’s stiff but workable. Don’t add too much water, or you could end up with a weaker final product.
Pouring and Finishing
For structural integrity and a professional appearance, work quickly and efficiently to transfer mixed concrete into forms or molds before it starts to set. You can use concrete vibrators for larger jobs to eliminate air pockets, which could lead to cracks later.
To finish the concrete, level and smooth the surface with screeds for broad surfaces and trowels for edging. Avoid cracks by incorporating control joints, including grooves, at regular intervals to account for shrinkage as it dries.
Curing Concrete
Curing directly impacts the concrete’s strength and durability. Allow the concrete to cure for one to two weeks by keeping it damp. Shield fresh concrete from rain, wind, excessive heat, and freezing temperatures, as they can damage the surface’s quality and strength.
Choosing the Right Concrete Mix
Different jobs call for different types of concrete. We recommend using Quikrete for your home improvement projects.
- Large projects: For patios, slabs, or other large projects where you need strength and durability, use a standard concrete mix, such as Quikrete Concrete Mix in the yellow bag.
- Countertops: Choose Quikrete Countertop Mix in the blue bag, which is specifically designed for countertops. It minimizes shrinkage to achieve a smooth, attractive surface.
- Small projects: Opt for a fast-setting mixture, including Quikrete Fast-Setting Concrete mix in the red bag, if you have a smaller project or require a fast turnaround.
You can also use Quikrete’s Concrete Calculator to determine how many bags you will need for your project.
Today’s Homeowner Tips
Concrete is a low-budget and straightforward project, so it can work well as a DIY project. Do your research ahead of time and take on simpler projects first before attempting complex pours.
Concrete Vs. Cement
Cement is an ingredient in concrete, while concrete is the finished product. Concrete owes its strength, durability, and versatility to the chemical reaction of cement, aggregate, air, and water mix. Using cement alone won’t provide the necessary structural integrity for most construction applications.
While you’ll usually use cement to create concrete or mortar, it can also be suitable for quick fixes, patching jobs, or artistic applications. Concrete is ideal for building foundations, walls, slabs, driveways, patios, sidewalks, countertops, garden planets, and more.
Final Thoughts About Concrete Vs. Cement
Although professionals and homeowners use the two words interchangeably, cement and concrete are very different substances. You can’t use them in place of one another. If you’re uncomfortable mixing or working with concrete, we recommend contacting a professional to help with the project.
FAQs About Cement Vs. Concrete
What is the main difference between cement and concrete?
The main difference is cement is an ingredient in concrete, while concrete is the finished product.
What is cement made of?
You make cement from lime, silica, alumina, iron oxide, and gypsum. You can make it in various ways, including burning limestone and clay in a kiln. Then you pulverize it into a powder.
Can you use cement instead of concrete?
No, you shouldn’t use cement alone as a concrete substitute. Cement requires mixing with sand, aggregate, and water to produce concrete with compressive strength.
What is the cement-to-concrete ratio?
A typical concrete mix contains about 7% to 15% cement plus sand, gravel, or crushed stone aggregates, and water. The higher the percentage of cement, the stronger but more difficult the concrete is to work with. Higher-strength concrete also has higher amounts of shrinkage.
Is cement cheaper than concrete?
Cement alone costs less than pre-mixed concrete containing aggregates. However, separately buying cement and aggregates involves more work and usually only makes sense for large projects.
How long does concrete last vs. cement?
Properly mixed, poured, and cured concrete has an average life of 50 to 100 years. Reinforced concrete may have a longer service life span.
