Rationale

Section 7.2.2.4 of ASTM C1780-25a includes specific installation instructions for ‘large-format units’. The standard, however, does not contain any information on what constitutes a ‘large-format unit’. Through discussion of the task group, it was decided that the installation procedure outlined in Section 7.2.2.4 should be used for units that have a face area of 1 square foot (144 square inches) or greater. This ballot proposes to modify 7.2.2.4 to include the face area size criteria for a 'large-format unit'.