Screed vs Concrete: Difference between Concrete and Screed

5th June 2024

Screed and concrete are both used for construction projects, so how do they differ from one another?

Simply put, the main difference between screed and concrete is their strength. Concrete is solid and capable of withstanding heavy loads and structural stress, making it ideal for foundations and support structures. However, people use screed as a top layer to create a level surface for flooring because it is smoother and weaker.

These two materials appear similar, but each serves a unique purpose crucial for various construction projects. Whether you’re laying the foundation for a new commercial building or simply renovating your home’s flooring, knowing when to use screed versus concrete can make all the difference in the outcome of your project.

As David Allan Coe wisely said, “It is not the beauty of a building you should look at; it’s the construction of the foundation that will stand the test of time.”

In this blog, we’ll walk you through the key properties of screed and concrete, their uses, and why understanding their differences is essential for any building endeavour. Let’s dive in!

Key Properties of Screed and Concrete

To understand the differences, one needs to understand the materials: their components, properties, and use in construction projects.

Key Properties of Screed:

Smooth Finish:

Screed provides a flat, smooth surface, ideal for finishing floors.

Thin Layer:

It is typically applied thinly, usually between 25 to 40mm.

Fast Setting:

Screed sets faster than concrete. This allows for quicker installation of floor coverings.

Flexibility:

Different types of screed can be used depending on the desired floor finish and specific requirements.

Key Properties of Concrete:

Strength:

Concrete has high compressive strength. It makes it suitable for load-bearing structures.

Durability:

It can withstand harsh environmental conditions, including drying cycles and chemical exposures.

Versatility:

You can mold concrete into various shapes and sizes.

Cost-effective:

It costs relatively less compared to other building materials.

To know more about liquid screed and concrete, their properties and key differences, you can check out our other blog:

Key differences Between concrete and liquid screed

Moving forward, let’s discuss the physical differences between concrete and screed:

The Physical Difference Between Concrete and Screed

Concrete and screed differ in composition, texture, strength, thickness, and drying time. This influences their applications.

Concrete

Concrete is composed of cement, water, and larger aggregates like gravel. Gravel has a rough texture and high compressive strength. It is used for structural elements like foundations and slabs. Its thickness typically ranges from 100 mm to several meters. Concrete has a longer drying time so that it will be finished in 28 days.

Screed

In contrast, a screed is made of water, cement and fine sand. This results in a smooth finish, which is ideal for laying floor coverings. It has a lower compressive strength (20- 30 MPa), is applied in thin layers (25- 40 mm). Screed sets faster, allowing floor coverings to be laid in 24-48 hours. The screed is not intended for structural support but for providing a level surface over concrete.

Let us explain it to you in simple terms:

Property	Concrete	Screed
Composition	Cement, water, large aggregates	Cement, water, fine sand
Texture	Rough	Smooth
Compressive Strength	High (20-40 MPa)	Lower (20-30 MPa)
Typical Thickness	100 mm to several meters	25 to 40 mm
Drying Time	Longer (28 days to full strength)	Faster (24-48 hours for fast-drying screeds)
Primary Use	Structural elements	Finishing layer for floors
Durability	High, withstands heavy loads	It relies on underlying concrete

Why use Screed Instead of Concrete?

Using screed instead of concrete is beneficial when a smooth, level finished surface is required. There are many reasons to use screed instead of concrete. Some are listed below:

Surface Finish:

Screed creates a smoother finish compared to concrete. It is essential for laying floor coverings.

Precision:

Screed allows for precise levelling of the floor. The precision guarantees an even floor with no uneven surfaces and bumps.

Efficiency:

Screed can be installed in much less time than concrete. Most people prefer screed because it dries much faster than concrete. This lesser drying time allows for the following construction projects to commence faster. Thus reducing the project timeline.

Versatility:

Screed has different types suitable to various needs. E.g., bonded and unbonded screed, floating screed, anhydrite screed, heated screed, etc. All these different types offer unique construction solutions for various flooring needs.

Can I Use Concrete Instead of Screed?

Absolutely! Using concrete instead of screed depends on the application. Concrete would be the preferred option for construction purposes. Especially for structural requirements. On the contrary, you can utilize screed atop a concrete foundation to establish a smooth upper layer. While concrete is excellent for structural support, it does not provide the smooth level finish that screed offers. Here’s why you can use concrete instead of screed for your construction projects.

Structural Requirements:

Concrete is preferable for surfaces that need significant loads due to its high compressive strength and durability.

Outdoor Use:

Concrete’s durability and strength are ideal for external applications like driveways or pathways.

Industrial Floors:

The robustness of concrete provides an advantage in industrial settings where heavy machinery is used.

However, screed remains the better choice for interior flooring where a flat, smooth surface is essential for laying carpets, tiles, or other finishes.

Is Screed Stronger Than Concrete?

No, screed is not stronger than concrete. In terms of compressive strength, concrete is generally more robust than screed. Concrete withstands significant loads and structural stress. This makes it ideal for foundations and other load-bearing elements. Screed; however, it is not for structural support. Instead, it provides a smooth, level surface for floor finishes.

What Role Do Concrete and Screed Play in The Aesthetics of My Project?

Both concrete and screed play significant roles in shaping the aesthetics of a project in different ways:

When considering the aesthetics of your project, the screed plays a pivotal role in creating a smooth, level surface that acts as a perfect canvas for finishing touches. Concrete is rough and uneven. Screed provides a superior level of visually pleasing and functionally effective finish. Its fine-grained composition allows for a more uniform appearance, enhancing the overall look of tiles, wood flooring, or other surface materials that will be installed atop it.

By ensuring a flatter and more stable base, the screed helps to avoid potential issues like cracks and gaps that can detract from the visual appeal of your completed project. Investing in high-quality screed contributes to a more polished and elegant finish and ensures that your aesthetic vision is fully realized.

What are the applications of screed and concrete?

Applications

Both concrete and screed have different applications, which differ for different projects. Some of them are:

Concrete

Building Foundations: Essential for residential and commercial structures, building foundations provide the necessary stability and load distribution to ensure the integrity and longevity of the building. Properly constructed foundations prevent settling and structural damage.
Walls: Concrete is crucial for providing structural support in both load-bearing and non-load-bearing walls. Load-bearing walls transfer the weight from the roof and upper floors down to the foundation, while non-load-bearing walls primarily serve as partitions.
Flooring: Concrete flooring is ideal for areas with heavy loads, such as warehouses and industrial settings. Its durability and strength make it capable of withstanding high traffic and heavy machinery without significant wear and tear.
Pavements and Driveways: Commonly used in urban areas, concrete pavements and driveways offer durable, long-lasting surfaces that can handle continuous vehicle traffic and harsh weather conditions. They require minimal maintenance compared to other materials.
Civil Engineering Projects: Concrete is integral to bridges, dams, and other large-scale infrastructure projects. Its strength and durability make it the material of choice for constructing resilient structures capable of withstanding immense pressures and environmental factors.

Screed

Interior Flooring: Screed is used to ensure a smooth, level surface for various types of flooring, including carpet, tiles, or wooden flooring. It creates a uniform base that enhances the aesthetic appeal and functionality of the final floor covering.
Underfloor Heating Systems: Screed provides a level base for efficient heat distribution in underfloor heating systems. It encapsulates the heating elements, allowing for even heat transfer and improved energy efficiency.
Renovation Projects: In renovation projects, a screed is used to level uneven concrete substrates before applying new finishes. This process ensures that the new flooring adheres properly and looks flawless.
Outdoor Areas: Screed is also used for outdoor areas such as balconies and terraces, where a durable, level finish is required. It creates a flat surface that can withstand outdoor elements and provides a solid base for additional coverings.
Final Finish: In some cases, the screed is the final finish for concrete floors in commercial spaces. When polished or treated, screed can create a sleek, attractive, functional, and aesthetically pleasing surface.

Why is Professional help required to choose between screed and concrete?

When applying screed and concrete, the importance of hiring a professional cannot be overstated. While DIY efforts might save some upfront costs, the risks can lead to long-term pitfalls that outweigh the initial savings. Professional screeding and concrete laying require precision, expertise, and specialised tools. This ensures the highest quality and durability of the final product. This is where The London Screed Company excels, setting the standard for excellence in the industry.

We bring experience and knowledge to every project, ensuring that each installation meets rigorous quality standards. Their trained professionals understand the complexities involved in properly preparing the substrate, selecting the right type of screed or concrete, and applying the necessary techniques to achieve a flawless finish. They also use advanced tools and machinery that are often inaccessible to the average DIY enthusiast, guaranteeing a level of accuracy that can significantly prolong the life and look of your floors.

In conclusion, while tackling a screeding or concreting project on your own may seem appealing, the expertise and precision provided by professionals like The London Screed Company ensure superior, long-lasting results. For construction or renovation projects, entrusting your flooring needs to a team saves you time and potential errors. Including the peace of mind that comes with a job well done.

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