Installation Guide

Skim coat is recommended to be 1/8"

- 1/4" 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.

¹ See IRC Table R703.4, IBC §2101.2 and

§1405.10

VINYL AND RESILIENT FLOORING (Interior Application Only)

Materials Required

1 | Fasteners

• Minimum 7/8” long galvanized or polymer-coated 18-gauge chisel point staples

with 1/4”crown.

• Minimum 7/8” long galvanized ring shanked underlayment ooring nails.

• Fasteners should be long enough to reach the bottom of the suboor, but not

penetrate it.

• Avoid using resin, rosin or cement-coated fasteners that can discolor vinyl ooring.

2 | Patch

• Use the cement-based, rapid-setting patching compound recommended by the

oor 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 ooring. For best results, remove existing oor covering,

especially if it is in poor condition.

• If installing HardieBacker cement board over existing oor, ensure the oor is at

and oor covering is thoroughly adhered to the suboor.

On all ﬂoors:

• Ensure suboor is not damaged. Replace any loose, warped, uneven or damaged

sections of oor.

• Make sure suboor is dry, level and fastened correctly. All fasteners must be

countersunk or ush with the suboor. All seams or other areas that are not level

must be sanded at.

• Suboor must be free of all debris, oil, grease, paint or other foreign substances.

2 | Basements and crawl spaces

• Crawl spaces must be well ventilated with a minimum of 18” between the ground

and joists. A vapor barrier over the ground is required.

5 | English