Installation Guide - James Hardie Pros

1/4 in square-notched trowel. Mastic can also be used with a 5/32 in V-notched trowel. • Use the fastener pattern as a guide. Fasten HardieBacker cement board with specified nails or screws (as listed in “Materials Required") every 8 in over the entire surface. Keep fasteners between 3/8 in and 3/4 in from board edges and 2 in from board ...

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