what is the top layer of concrete called
Screed Screed has three meanings in building construction: 1) a flat board (screed board, floating screed) or a purpose-made aluminium tool used to smooth and true materials like concrete, stucco and plaster after it has been placed on a surface or to assist in flattening;[1] 2) a strip of plaster or wood applied to a surface to act as a guide for a screed tool (screed rail, screed strip, screed batten); 3) the material itself which has been flattened with a screed (screed coat).[2] In the UK, screed has also come to describe a thin, top layer of material (traditionally sand and cement), poured in site on top of the structural concrete or insulation, on top of which other finishing materials can be applied, or it can be left bare to achieve a raw effect.