scratch coat


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scratch coat

[′skrach ‚kōt]
(engineering)
The first layer of plaster applied to a surface; the surface is scratched to improve the bond with the next coat.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

scratch coat

In three-coat plastering, the first coat of plaster, which is then scratched to provide a bond for the second (brown) coat.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.
References in periodicals archive ?
The key is to put on enough mortar to create about a l/2-in.-thick layer when the stone is pressed against the scratch coat. If any mortar oozes out around the edges, knock it off with the trowel so it doesn't get in the way of grouting.
Generally, stucco is built with four separate coats--two base coats (the scratch coat and brown coat) and two finish coats (the wash coat and dash coat).