The lining of concrete formwork can be used to impart a smooth or patterned finish to the concrete surface; to absorb moisture in order to obtain a drier surface; or to apply a set-retarding chemical, which allows the aggregate to be exposed.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
A lining on the concrete-face side of formwork either: (a) to absorb water from the concrete, (b) to impart a patterned finish or smooth finish to the concrete surface, or (c) to apply a set-retarding chemical to the formed surface.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.