The Differences Between Concrete & Screed Explained

What is Screed?

Screed and concrete are similar in some regards as they are both made from the same raw materials – cement, water and aggregate. Screed, however, is applied as a top layer to a concrete base often as a finish or to level the floor prior to the installation of tiling, carpets etc. This thinner layer of concrete is typically poured over the base floor in order to form a smooth and strong coating.

Whilst the materials and ratios of each screed mixture can be adjusted to fit specific project requirements, such as taking a more liquid form when used indoors or a denser form for outdoor use, there are generally considered to be four different types of screed. Underfloor screed is perhaps the most common usage case for screed, where it is poured directly over heating pipes rather than insulating material – good heat flow is allowed for due to the thin nature of this type of screed.

Floating screed is rather similar to underfloor screed. It is applied directly to a layer of insulation which has a damp proof member over it, allowing for the screed to have a layer of separation from the insulation.

Bonded screen is applied directly to a concrete base following the use of a strong primer or bonding ages, allowing for an extremely strong hold. Unbonded screed, however, is usually applied to damp proof membranes in order to create a form separation between the screed and concrete base.

What Is the Difference Between Concrete & Screed?

Screed is often confused with concrete, and it’s easy to see why. Whilst they may consist of similar materials, their uses are vastly different.

The sheer level of strength concrete is able to produce means it can withstand immense pressure over long periods of time, which is why it is commonplace in the construction industry. Comparatively, screed is used when a functional floor or specific flooring type is wanted as opposed to a plain concrete floor.

Although they can often share a likeness, there is no definitive answer as to which is the better material since they both have completely different properties that make them suitable for different projects. Their main differences are that of their function, concrete is used for strength whilst screed is used as a finishing layer. 

The Benefits of Using Concrete

A large benefit of concrete that is not often discussed yet has been key towards making it the most man-made material on Earth, is it’s hardening temperature. Concrete is able to set at regular room or ambient temperatures, meaning it can be used irrespective of inclement weather.

Due to using harder and bigger aggregates in its creation, concrete consists of a coarser mixture which leads to greater durability and longevity, making it ideal for construction and structural projects. Concrete is generally cheaper than screed, however it may not always be the most appropriate option.

Concrete is very economical and inexpensive, with easily accessible raw materials which are widely available around the world at low cost. Furthermore, concrete structures are considered to be relatively low, to zero, maintenance. Concrete does not require coating or painting for optimum strength or protection as other materials might. This further enhances the economic benefits of concrete in both terms of time and money.

Axtell concrete poured from truck

 

The Benefits of Using Screed

Screed is able to provide a much smoother finish than the coarse and rough feel that concrete provides. Applying screed over floor heating pipes is also perfectly safe and is ready to accept foot traffic within 24 to 48 hours from application – meaning less hold-ups on the worksite.

Screed is a premixed, ready-made material meaning that there is no need for extra time and resources to be used up onsite in the creation of the product. The mixture has self-levelling properties meaning you won’t need to worry about levelling the product after application and this, in conjunction with the mixtures ability to be pumped directly onto the surface that needs application, means an overall minimal hit to your workforce.

Whilst concrete may often be cheaper than screed, simply applying screed over your damaged concrete flooring can often be less troublesome and sometimes even cheaper than completely redoing your concrete floor.

Axtell floor screed smoothing at construction site

 

The Physical Differences Between Concrete & Screed

As previously mentioned, screed and concrete are both made up from the same core materials, however the type of aggregate used is what creates their main differences.

Concretes use of a much coarser aggregate within its mixture provides an end product with a similar texture and feel, creating a more physically strong and durable result.

Comparatively, screed uses a finer sharp sand aggregate within its mixture, resulting in a smoother and more tightly packed texture that makes it perfect for being used as a top layer to concrete flooring.

Visually, you should be able to instantly notice concretes rougher appearance and observe the small bits of gravel and stone within, with screed appearing to look noticeably finer.

What Types of Projects Can Concrete and Screed Be Used For?

Due to the discussed benefits of both screed and concrete, both have their optimal uses and different types of projects that may favour one over the other, or often both simultaneously.

Concrete is best suited to construction and structural projects whereby strength, resilience and durability are the most important factors. Uses such as the creation of pavements, flooring and foundations are great examples of projects where concrete is commonplace.

Whereas screed is generally used as a layer on top of concrete, however it is generally found within projects where high footfall and aesthetics are more of a concern. Since it is often used prior to the laying of carpets, tiles etc it is common to involve screed in most flooring-based projects, as well as acting as a top-layer to any underfloor heating or insulation.

How to Determine Whether Your Project Requires Concrete or Screed?

To determine whether your project will require concrete or screed, consider its sole purpose and what it will be exposed to. If you are planning to level a floor space and add wooden panelling over it, screed is most likely to be required to achieve optimum end results. However, if you are looking to create an outdoor pavement in your garden, that’ll stand the test of time and seek longevity then concrete is a solid choice. Make use of our Screed calculator to find out which mix we recommend using and how much you’ll need, with a quote sent directly to you today.

Explore Axtell’s Concrete & Screed Services

With over 20 years’ experience in the industry, Axtell are a trusted supplier in providing concrete & screed services across the South East of England.

Whether it’s a large construction project or a small DIY job laying a floor, Axtell offer high-quality, expert concrete screed pumping services with an experienced team on hand to complete the job at a competitive price. For more information, check out our Concrete Calculator to identify how much mix and which type your job will require, or alternatively to request a free quote, please don’t hesitate to get in contact with us today.

Axtell delivering concrete screed to construction site