screed

thumb|The screed on this Paver (vehicle)|paver spreads and smooths the asphalt.

Screed has three meanings in building construction: A flat board (screed board, floating screed) or a purpose-made aluminium tool used to smooth and to level materials like concrete, stucco and plaster after they have been placed on a surface or to assist in flattening; 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); The material itself which has been flattened with a screed (screed coat). In the UK, screed has also come to describe a thin, top layer of material (sand and cement, magnesite or calcium sulphate), poured in place on top of the structural concrete or insulation, on top of which other finishing materials can be applied, or the structural material can be left bare to achieve a raw effect.