Installation Guide

(0.375 in HD) or ribbed wafer head corrosion
resistant screws spaced a maximum of 8 in OC.
The maximum weight of the overlayment (tiles,
stones and veneers) is not to exceed the code
limit of 15 lbs/sq ft. Exterior application is limited
to HZ10
®
product zone only.
Follow installation procedure in accordance
with the stone and mortar manufacturer’s
recommendations.¹ Stones must be free of any
substance that may impede proper adhesion.
Skim coat is recommended to be 1/8 in - 1/4 in
thick and the tile/stone is to be installed while
the skim coat is wet.
CAUTIONS: This product shall not be used in the
following applications:
• As a backer board in balcony railings and
balcony parapet walls.
• HardieBacker 500 may not be used to a height exceeding through the second-
story above grade or greater than 30 feet above grade.
VINYL AND RESILIENT FLOORING (Interior Application Only)
Materials Required
1 | Fasteners
• Minimum 7/8 in long galvanized or polymer-coated 18-gauge chisel point staples
with 1/4 in crown.
• Minimum 7/8 in long galvanized ring shanked underlayment flooring nails.
• Fasteners should be long enough to reach the bottom of the subfloor, but not
penetrate it.
• Avoid using resin, rosin or cement-coated fasteners that can discolor vinyl
flooring.
2 | Patch
• Use the cement-based, rapid-setting patching compound recommended by the
floor covering manufacturer.
• Do not use a gypsum-based patch. Follow the patch manufacturer’s instructions.
Preparation for Underlayment
1 | Ensure subfloor is structurally sound and properly installed
On existing floors:
• HardieBacker
®
cement board may be installed under or over Vinyl Composition
Tile (VCT) and other resilient flooring. For best results, remove existing floor
covering, especially if it is in poor condition.
• If installing HardieBacker cement board over existing floor, ensure the floor is flat
and floor covering is thoroughly adhered to the subfloor.
On all floors:
• Ensure subfloor is not damaged. Replace any loose, warped, uneven or damaged
sections of floor.
• Make sure subfloor is dry, level and fastened correctly. All fasteners must be
countersunk or flush with the subfloor. All seams or other areas that are not level
must be sanded flat.
• Subfloor must be free of all debris, oil, grease, paint or other foreign substances.
5 | English
¹ See IRC Table R703.4, IBC §2101.2 and §1405.10