Liquid Screed vs. Traditional Screed

Posted on: 15th December 2021

Case Study: Liquid Screed in a Renovation Project
Contents

Last updated: June 2026

Liquid or pumpable screeds are a relatively new invention and can be an excellent alternative for traditional sand and cement screeds. Their popularity is increasing, primarily because they can be laid to a thinner depth and are far quicker to lay than traditional screeds, and they’re especially popular in use with underfloor heating. But what exactly is liquid screed, what’s it made of and how is it different traditional screed? How do you know which screed is right for your construction project and budget? Read on to find out.

In brief: Liquid screed is pumped into place rather than laid by hand, self-levels, and can cover around 25 square metres in about 20 minutes. It is more expensive per square metre than traditional sand and cement screed, but savings on labour generally make the overall cost comparable. It works especially well with underfloor heating, as it flows around pipes and conducts heat more efficiently. The main trade-off with calcium sulphate (gypsum) liquid screed is that the surface forms a layer of laitance as it dries, which needs to be sanded off before the floor finish can go down. Cement-based liquid screeds avoid this step but cost more and are less widely available.

What is a Liquid Screed and How is it Different to a Traditional Screed? 

Screeds are not a structural element of your building; they are applied over the flooring surface to provide a smooth, level and flat surface that the finishing materials, such as carpeting or tiles, are applied to. If you are using underfloor heating it will be laid under the screed, which is poured over the top. 

Traditionally a screed would have been laid by shovelling in the screed mix and then levelling it with a screeding bar and/or polyurethane float. Liquid screeds are ready-mixed, delivered to site where they are then pumped into the room and poured across the floor. This liquid finds its own level so will be perfectly level and will be hard enough to walk on in about 72 hours, although it will take longer before it is completely dry. 

 

How the Screed Market is Changing!

Different Types of Liquid Screed 

The most common type of liquid screed has calcium sulphate as the active ingredient, making up around a third of the volume. This becomes gypsum when water is added, and as a result can be referred to as a “calcium sulphate screed”, “gypsum screed” or even “anhydrite screed” which refers to the form of the mineral – anhydrous calcium sulphate – which is used. 

More recently cement based pumped screeds have become available. These can be pumped like a gypsum screed, but do not have the downsides.  

Different manufacturers and suppliers (Tarmac, Breedon, Cemex, McGraths etc) have different proprietary products (Topflow Screed, Belitex, Cemfloor, etc) so there is variation, but they will broadly fall into these following categories: 

  • Traditional cement screed 
  • Pumpable calcium sulphate screed (AKA Anhydrite screeds) 
  • Pumpable cement-based screed 

The choice of which one to choose is based on the different pros and cons of the various options.  

Liquid Screed vs. Traditional ScreedBenefits of Traditional Screeds 

  • Possible to self-mix so you can ensure the right amount and are not dependant on an outside delivery 
  • Can be ready mixed and delivered to ensure consistency while reducing significant amounts of effort and time  
  • Possible to create a flat surface which is not level; this can be necessary particularly in wet rooms for example 
  • Material costs are cheap – certainly the cheapest of the screed options 

Benefits of Pumped Calcium Sulphate Screed 

  • For example Gyvlon
  • Very quick to lay/pour – a 25m2 area will take around 20 minutes start to finish 
  • While the material costs are typically about twice that of traditional screed because it is so quick to lay – savings can be made on labour and time which means the cost are broadly the same 
  • Can be laid as thin as 35mm which reduces material costs and means that heat from under-floor heating is more effective 
  • It is very level – much more so than is possible with a traditional screed even with an experienced professional 
  • Calcium sulphate is less prone to shrinking which means there is less need for expansion joints, and large tiles laid on it will be less prone to cracking 
  • Under-floor heating is more effective, not only because it is not heating a larger depth/volume of screed, but because the liquid flows all around the pipes so heat transfer from the pipes are more effective 
  • Dries about 1mm/day up to 40mm depth (20°C, 65% RH)

Disadvantages of Calcium Sulphate Screed 

  • The floor surface needs to be prepared before the finished floor material can be installed. A substance called laitance needs to be removed  
  • Calcium Sulphate is water-soluble, so anhydrite screeds are not compatible with wet conditions and shouldn’t be installed in e.g. bathrooms or kitchens.
  • Most suppliers will not allow DIY laying; they will insist that an experienced contractor be used to measure and pour the screed 

Benefits of Pumped Cement Screed 

  • For example Cemfloor
  • Like Anhydrite screeds, pumped cement creeds are also suitable for use with underfloor heating, and
  • Once dry, it doesn’t need surface preparation (whereas a calcium sulphate screed does), before laying the finished floor surface, and can even be used as a finished floor by itself
  • Harder wearing and more suitable for industrial floors than calcium sulphate screeds
  • Compatible with wet areas like commercial kitchens and wet rooms

Disadvantages of Pumped Cement Screeds 

  • Availability is currently limited  
  • The material cost is about 20% higher than a calcium sulphate screed although in a similar way this can be made up with a reduction in labour time  
  • They require more expansion gaps than a calcium sulphate screeds as they’re slightly more prone to shrinkage

It is easy to see why using a liquid screed has become so popular. It is quick and requires much less labour than a traditional screed. It is not effective on a small scale or where there needs to be a slope on the floor though, but almost anywhere else it is fast becoming the preferred solution.

For information on high-quality screeding tools used by professional screeders and groundworkers to level, dapple and spray free flowing liquid screeds, click here!

Frequently Asked Questions

Self-compacting concrete, also known as self-consolidating concrete or SCC, is a highly fluid form of concrete that flows and levels under its own weight without needing vibration or mechanical compaction. It achieves this through the addition of superplasticisers during mixing, which give the material a much higher flow rate than traditional concrete while keeping the aggregate evenly suspended rather than allowing it to settle. It is used across a wide range of applications from domestic foundations to large-scale civil engineering projects.

Traditional concrete needs to be compacted after placing, usually with a vibrating poker, to remove air voids and ensure the mix fills the formwork fully. SCC does this by itself as it flows into place, which removes the need for vibration equipment and the labour that goes with it. It does however need dappling with a dapple bar. The result is typically a stronger, more consistent finish with fewer surface voids, and the process is significantly faster on pours where access for vibrators would be difficult.

The key advantages are reduced labour, faster placement over large areas, no vibration equipment needed, lower noise levels during the pour, and better access to areas where traditional compaction methods would be difficult or impossible. SCC can also be supplied with an integral waterproofing admixture, making it suitable for below-ground structures where water ingress is a concern. Reduced plant requirements also mean fewer health and safety hazards on site during the pour.

Yes. Like all concrete, SCC needs to be protected as it cures to prevent the surface drying faster than the rest of the slab. If surface water evaporates too quickly, the top layer becomes weaker and prone to cracking and dusting. A curing agent is sprayed onto the fresh surface immediately after the pour to form a membrane that slows this evaporation and allows the slab to cure evenly throughout. Without it, even a well-mixed and well-placed SCC pour can produce a surface that underperforms.

The main tools required are screed levelling tripods to set the pour depth before the concrete goes down, dapple bars to work the surface after pouring and achieve a smooth finish, and a pressurised sprayer to apply the curing agent once the surface has been finished. The dapple bar and sprayer steps are critical to the final quality of the floor, and using the right tools for each stage makes a noticeable difference to the result.

SCC is used wherever traditional concrete placement is difficult or where a high-quality, consistent finish is needed with minimal labour. Common applications include foundations, underground structures, columns and walls with dense reinforcement, bridge components, and tunnel linings. On smaller domestic and commercial projects it is increasingly used for floor slabs and footings where the speed of placement and quality of finish justify the slightly higher material cost compared to traditional concrete.

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