Installation Guide

5 | English
WOOD FLOOR INSTALLATION (Continued)
3 | Attach the HardieBacker
®
Cement Board with HydroDefense
™
Technology to the subfloor
• HardieBacker
®
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
subfloor using a 1/4 in. square-notched trowel.
• Install HardieBacker
®
Cement Board with HydroDefense
™
Technology.
• Embed cement board firmly and evenly in the wet mortar (see “Materials
Required”).
• 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. to 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”).
• Fill all joints with mortar (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.
WOOD FLOOR DETAIL
The floor assembly (floor joists and subfloor) must be engineered not to exceed the
L/360 deflection criteria (L/720 for natural stone), including live and dead design
loads, for the specific joist spacing used.
Joist spacing
max. 24 in.
A
F
C
D
E
B
A
B
C
D
E
F
Tile bonding mortar
HardieBacker
®
Cement Board
with HydroDefense
™
Technology
Gap
Bedding Mortar
Wood Subfloor
Tiles
* Some application areas may require additional waterproofing. Refer to local building code requirements.