Work Item
ASTM WK87390

Revision of C1780-23 Standard Practice for Installation Methods for Cement-based Adhered Masonry Veneer


This ballot proposes several changes to sections in ASTM C1780 related to water resistive barriers:
1. Defining ‘primary’ and ‘secondary’ WRB. Primary is used to describe the inner-most layer of WRB – the one that is in contact with sheathing. Secondary is the outer layer that is primarily a bond break between the primary and scratch coat.
2. Revisions in Section 6.3 and 6.4 to use the terms ‘primary’ and ‘secondary’, along with cleanup to remove redundant Note 8. The information in Note 8 is covered in Section 6.4.1.
3. Revise language related to integrate WRB with flashing systems to ‘minimize’ water penetration.

Note that at the time that this ballot was issued, the current edition of this standard is C1780-23 but C1780-23a has been approved and will be issued soo. Changes in C1780-23a do not impact this ballot item.


Developed by Subcommittee: C15.05

Committee: C15

Staff Manager: Krista Robbins

Work Item Status

Date Initiated: 08-08-2023

Technical Contact: Nicholas Lang