ASTM C1063 is the ASTM standard that addresses the installation of lathing and furring for interior and exterior Portland cement-based plaster. It helps define a consistent basis for preparing plaster substrates so materials are installed in a reliable, workmanlike manner. For projects that use cement-based plaster, this specification matters because proper lath and furring installation can support performance, finish quality, and overall compliance with project requirements.

What is ASTM C1063?

ASTM C1063, Standard Specification for Installation of Lathing and Furring to Receive Interior and Exterior Portland Cement-Based Plaster, is a technical document focused on how lath and furring should be installed before plaster application. Its purpose is to provide a common set of installation requirements for assemblies intended to receive cement-based plaster. In practical use, the standard supports consistency in substrate preparation, which can help reduce installation variation and improve coordination among designers, contractors, and inspectors.

Where is ASTM C1063 used?

This standard is commonly used on projects where interior or exterior Portland cement-based plaster is applied over lathing and furring systems. It is relevant during substrate preparation, framing coordination, and plaster installation workflows, especially when the assembly must meet specified construction requirements. ASTM C1063 is often referenced in contract documents, quality control reviews, and field inspection activities where proper support for plaster finishes is important.

Why is ASTM C1063 important?

ASTM C1063 is important because it provides a recognized specification for a critical part of plaster assembly construction. Using a consistent standard can help improve compliance, support product and system evaluation, and reduce the risk of installation errors. For owners, contractors, and inspectors, it offers a clear technical reference when checking whether lathing and furring have been installed in a manner suitable for cement-based plaster applications.

• Installation of lathing and furring
• Interior and exterior plaster applications
• Portland cement-based plaster assemblies
• Quality control and field inspection reference
• Specification and procurement support