Concrete vs Liquid Screed: What’s the difference and which is right for your project?

When tackling a flooring project, whether it’s for a new build, renovation, or commercial space, choosing the right material is key to achieving the best finish, durability, and functionality. While concrete and liquid screed are both popular choices for creating subfloors, they serve different purposes and come with distinct benefits. Knowing these differences can help you make an informed decision for your project, or find the best screed company to handle your needs.

What is Concrete?

Concrete is a staple in construction, used worldwide for its strength, durability, and cost-effectiveness. Made from a mix of cement, sand, gravel, and water, concrete is typically laid thick to provide a solid, load-bearing foundation. It’s commonly used for structural elements like foundations, slabs, and exterior paving.

Concrete is ideal for applications where the floor or foundation needs to support significant weight or be resistant to wear. However, while concrete provides the strength needed for such tasks, it can leave a rough surface that often requires further treatment if a smooth, level finish is needed.

What is Liquid Screed?

Liquid screed, also known as flowing screed, is a more refined material, typically made from sand, cement, and water or anhydrite. Unlike traditional sand-cement screeds, liquid screed has a flowable consistency, which allows it to self-level, creating an even, smooth surface. A screed company often applies this layer over a solid subfloor, such as concrete, to create a high-quality base ready for final floor finishes.

Liquid screeding has grown in popularity thanks to its speed of installation and ability to produce an impeccable finish with minimal preparation. It’s also ideal for use with underfloor heating systems, thanks to its thermal efficiency and rapid heating response.

Key Differences Between Concrete and Liquid Screed

1. Purpose and Application

• Concrete is a structural material, providing the strength needed for load-bearing applications. It’s commonly used for foundations, exterior paving, and large slabs where durability is paramount.

• Liquid Screed, however, is a finishing layer designed to create a smooth, level surface. It is typically applied as a thin top layer over concrete or other subfloors, making it ideal for indoor spaces where a clean, flat surface is essential for laying the final floorin 

2. Layer Thickness

• Concrete is usually poured in thick layers (often several inches) depending on the required load-bearing capacity.

• Liquid Screed can be laid at much thinner depths, with some formulations requiring as little as 15mm. This makes liquid screeding a great option in projects where height limitations are a factor.

3. Drying and Curing Times

• Concrete requires a lengthy curing period, sometimes up to several weeks or months, before it reaches full strength. This can slow down the overall project timeline.

• Liquid Screed dries much faster and can typically support light foot traffic within 24-48 hours. Final floor finishes can often be applied within 7-28 days, depending on the screed type, depth and site conditions. A quality screed company will ensure the drying process is optimised, helping to keep projects on schedule.

4. Thermal Conductivity

• Concrete has limited thermal conductivity and is slow to respond to temperature changes, which can make it inefficient for underfloor heating.

• Liquid Screed excels in thermal performance, especially anhydrite or gypsum-based screeds, making it a top choice for underfloor heating systems. Its thermal properties enable efficient heat distribution across the floor, enhancing energy efficiency and comfort.

5. Finish Quality

• Concrete usually requires additional treatment to achieve a smooth finish, often needing grinding or polishing if the floor is to be used as an interior surface.

• Liquid Screed provides an impressively smooth and level finish due to its self-levelling nature, often requiring no additional smoothing before the final flooring layer is installed. This can significantly reduce time and preparation costs.

6. Ease of Installation

• Concrete installation is labour-intensive, involving mixing, pouring, and extensive levelling work. This can be challenging, especially for large areas or intricate layouts.

• Liquid Screed is much easier and quicker to install, especially when handled by an experienced screed company. Its flowable nature means it can reach tight spaces and create a seamless, level layer without extensive labour.

When to Choose Concrete

Concrete is the right choice when strength and load-bearing capacity are essential, making it suitable for structural elements, garages, outdoor areas, and foundations. Concrete offers longevity and resilience in high-traffic or load-bearing environments.

Use concrete when:

• Structural integrity is a priority.

• The flooring needs to bear heavy loads.

• The surface finish is not an immediate concern.

When to Choose Liquid Screed

Liquid screed is the preferred option for interior floors where a smooth, level base is essential, especially for flooring installations that demand precision, like tiles, hardwood, or carpet. It’s also the best choice for underfloor heating systems, thanks to its efficient thermal conductivity and responsiveness.

Use liquid screed when:

• A flawless, level surface is needed for final flooring.

• The project includes underfloor heating.

• Quick drying times and efficient installation are priorities.

Choosing the Right Screed Company

Whether you’re working on a residential or commercial project, selecting the right screed company is crucial to achieving the best results. A skilled screed company will not only help you choose between concrete and liquid screed but also ensure the materials are expertly mixed, laid, and cured. Their expertise in screeding will ensure that the flooring meets your exact needs, from structural stability to a smooth, beautiful finish.

Final Thoughts

While concrete and liquid screed both play key roles in construction and flooring, their differences make them suited to distinct applications. Concrete remains essential for load-bearing elements, while liquid screed is ideal for creating smooth, even surfaces in interior spaces, particularly where underfloor heating is involved. Working with a professional screed company will help you decide on the best material and installation approach, ensuring a floor that is both functional and flawlessly finished.