Guide to Portland Cement-Based Plaster
|Publication Date:||1 March 2016|
This guide provides information and recommends minimum expectations for satisfactory lathing and plastering. Architects, engineers, designers, specification writers, contractors, plasterers, and public authorities can use this guide to familiarize themselves with the plastering processes and also as an aid in specification writing. Stricter requirements based on long-term successful field service or controlled laboratory experimentation and documentation can be imposed when warranted. This guide also addresses the prequalification of plaster materials, tool and equipment requirements, mixture proportions, application procedures, types of finishes, and troubleshooting and repair.
Exterior insulation and finish systems are exterior wallcladding systems that consist of an insulation board covered with an integrally reinforced base coat and a textured protective finish coat. Portland cement may be used in these systems, but their application and suitability are not covered in this guide. Robert (1997) provides useful information on this class of product.
The use of one-coat portland cement-based plastering systems and other such proprietary portland cement-based systems are acknowledged; however, they are beyond the scope of this document, which addresses only traditional two- or three-coat portland cement-based plastering systems. Alternative nontraditional and proprietary portland cement-based plastering systems are addressed by ICC Evaluation Service, Inc. (2006). One-coat systems and other proprietary systems typically rely on a proven performance history within the environment and region in which they are intended to be used. Where required by code, proprietary products can get special approval with a published evaluation services report that specifies the installation procedure and allowed locations for its use.
Swimming pool plastering is considered an alternative, nontraditional form of portland cement-based plastering in this guide. While many aspects of this guide are relevant to swimming pool plastering, information specific to swimming pool plastering can be found in the American National Standard for the Plastering of Pools and Spas (ANSI/APSP/ICC/ NCP-12) and in reports by the Portland Cement Association (PCA EB049) and the National Plasterers Council (2011).