THE screed is a critical part of the build-up of any skilfully installed floor. And when it comes to it, not all screeds are created equal. Flowing screeds in fact have many advantages for both residential and commercial applications, being simple to install, quick to dry and ideal for underfloor heating systems.

The Flowing Screeds Association (FSA) says it’s on a mission to drive up skill levels in the sector and encourage more companies to get involved and more specifiers to see the benefits flowing screeds can offer for their projects.

Normally a flowing screed is the best screeding solution, compared to a semi-dry sand:cement screed. Even the perceived benefit of reduced cost for a sand:cement screed is often in fact not true, since a flowing screed can be poured very much more efficiently, requiring less time and less labour than the alternative. It will usually dry more quickly as well.

Since it’s poured as a liquid, for the vast majority of jobs, a flowing screed, whether of the anhydrite type or cement-based, will provide the ideal, perfectly smooth surface for the laying of a top layer, whether this is tiling or any other type of floorcovering.

It’s important however that correct procedures are followed if the best floor is to be achieved, providing the best possible surface for overlayment with whatever floor finish is required
Underfloor heating (UFH) screeds supply an energy-efficient method of comfortably heating a building. Liquid screeds can greatly enhance the benefits to be obtained from UFH systems, but these benefits are only maximised when the system is correctly designed and installed to the best standard.

The high performance of liquid screeds means that they will usually be thinner than traditional screeds but will still provide more durability and strength to cope with higher loadings or heavier traffic.

Since they’re manufactured under strict quality control systems, they also remove the risks associated with traditional sand/cement screeds which are very dependent on the quality of the mixing.

In an industry where we demand quality, it’s surprising, to say the least, that many traditional screeds are mixed on-site by counting shovel loads (presumably calibrated shovels). Even when mixed under controlled conditions off-site, there is a great reliance on the manual and very demanding process of physically compacting the material into the floor.

If a screed material isn’t compacted to the density required it will be far below the expected strength. With liquid screeds this is not a risk, a liquid needs no compacting, it is delivered to site already at the correct density.

Since liquid screeds are generally thinner, they allow more options to the specifier. They may use the thickness saved to introduce more insulation to the same floor thickness and so have a better thermal performance. On a tall building, the saving of 35mm per floor can amount to well over a metre on the structure which would be a huge saving in the cost of the facades and may even have structural benefits.

Perhaps the most recognised benefit though is that of improved performance to underfloor heating. Less thickness of screed allows a heating system to work more efficiently but this is further enhanced by the fact that liquid screeds conduct heat better and provide complete encapsulation of the heating pipes. All these things together make the response (warm up) time for a liquid screeded under floor heating system as much as four times as fast or more.

Many liquid screeds are faster drying than traditional materials, which obviously brings benefits to site programmes and allows floor finishes to be installed more quickly and safely.

To support its work to promote all these benefits of flowing screeds and drive up standards in the sector, the FSA is looking to recruit more members.

It points out, ‘All members have access to training courses, technical documentation, a free listing on the website, free advertising through FSA channels, a credit checking service, business advice, networking opportunities and use of the FSA logo on vehicles and marketing materials.

‘The FSA has also recently launched a technical query service, which is available to all in the industry, and provides information to anyone who has a technical query about a product or a project involving flowing screeds. We intend to answer requests for information from members within five working days.

Membership is open to manufacturers, including binder and system manufacturers, as well as screed contractors and applicators. There is also an associate membership category.’
membership@flowingscreedsassociation.com
www.flowingscreedsassociation.com