Installation Guide

English | 6
COUNTERTOP INSTALLATION
1 | Ensure the cabinets are level and secure
• Use minimum 1/2 in. thick exterior grade plywood subbase or equivalent,
positioned across the wood cabinet. Space between plywood supports
is not to exceed 16 in. on center.
2 | Determine the HardieBacker
®
Cement Board with HydroDefense
™
Technology layout
• Do not align cement board joints with plywood joints.
• Score and snap boards to required sizes and make necessary cutouts.
• We recommend an 1/8 in. gap from board edges and joints.
3 | Attach the HardieBacker
®
Cement Board with HydroDefense
™
Technology to the countertop
• HardieBacke
r®
Cement Board with HydroDefense
™
Technology has internal
waterproofing treatment. Does not require a moisture barrier*
• Apply a supporting bed of dry-set mortar or modified dry-set mortar to
plywood with a 1/4 in. square-notched trowel.
• Install HardieBacker
®
Cement Board with HydroDefense
™
Technology.
• Embed cement board firmly and evenly in the wet mortar.
• Fasten cement board with specified nails or screws (see “Materials
Required”) a maximum of 8 in. on center over the entire surface.
• Keep fasteners 3/8 in. and 3/4 in. from board edges and 2 in. in from sheet
corners.
• Set fastener heads flush with the surface, without overdriving.
4 | Joints and penetrations
• Seal fixture penetrations, plumbing penetrations and abutments to dissimilar
materials with flexible sealant (see “Materials Required”).
• Prior to setting the tile, fill all joints with the same mortar used to set the tiles
(see “Materials Required”). While mortar is still workable, embed 2 in. wide
high-strength alkali-resistant glass fiber tape in the mortar and level.
• Do not use all-purpose joint compound or paper tape.
• When complete waterproofing is required, seal all joints, edges and fastener
penetrations with a liquid waterproofing membrane. Follow the liquid
waterproofing membrane manufacturer application instructions.
5 | Exterior Countertop application (limited to HardieBacker
®
Cement
Board with HydroDefense
™
Technology in HZ10 climate zones
‡
-
additional details on page 6)
• Follow countertop installation steps 1 through 4.
• DO NOT use mastic (organic adhesives) in exterior applications.
* Some application areas may require additional waterproofing. Refer to local building code requirements.