Traditional screed generally consists of either a 1:3 or 1:4 cement to sand ratio which complies with BS 8204-1.It can be mixed with polypropylene fibres (PPF) for reinforcement or in some cases a D49 metal mesh is used instead of the PPF as reinforcement.
Floating screed is most commonly used in residential properties as the screed is applied on top of a layer of thermal/acoustic insulation. The insulation is usually applied on to the DPM. Minimum thickness 75mm and 65mm is acceptable for domestic housing.
Bonded screed is fully bonded to the substrate using a bonding agent or a primer. It is most commonly used in areas that will experience heavy loading. 25mm-40mm – can go up to 200mm
The screed layer is not bonded to the base, but instead it is applied to a Damp-Proof Membrane (DPM) or polythene, separating the screed from the concrete. 50mm-70mm – can go up to 200mm
Calcium sulphate and cement based liquid floor screeds are phenomenal screeding products which have revolutionised underfloor heating systems, allowing super fast installation and smooth, professionally levelled, screeds.