Screed is a thin, top layer of material laid over a concrete subfloor, that is traditionally made of sharp sand and cement, similarly to concrete. Industrial screed can be used for more heavy duty applications by using a more coarse 6-10mm aggregate. It is used to cover structural flooring concrete, and can be applied to either a solid, in-situ or precast concrete floor slab. It can also be laid on top of insulating materials, and is ideal for covering underfloor heating pipes. It’s purpose is to provide a smooth, flat surface that other finishing materials, such as carpet, tile or floor boards, can then be laid on top of. Not only that, but it can also help to even out a floor surface, to ensure it is safe and level; as a rule of thumb the level of a floor should not vary more than 5mm over the space of 3 metres.