Installation Guide

7 | English
BASIC COMPOSITION
90% Portland cement and sand with
selected additives. Contains no asbestos,
formaldehyde, gypsum, paper facing, or
abrasive aggregate.
1/4 in HardieBacker cement board:
Sheet size: 3 ft x 5 ft (EZ Grid
®
board)
and 4 ft x 8 ft
Thickness: 1/4 in
Weight: 1.9 lbs. psf (9.3 kg/m2)
Complies with ASTM C1288 & ANSI
A118.9
HardieBacker
®
500 cement board:
Sheet sizes: 3 ft x 5 ft and 4 ft x 8 ft
Thickness: 0.42 in
Weight: 2.6 lbs. psf (12.7 kg/m2)
Complies with ASTM C1288 & ANSI
A118.9
MATERIALS REQUIRED
1| Mortar
For floors:
• Latex or acrylic modified thinset
(complying with ANSI A118.4).
• Dry-set mortar for use between
subfloor and cement board only
(complying with ANSI A118.1).
For walls and countertops:
• Latex or acrylic modified thinset
(complying with ANSI A118.4).
• Type 1 mastic (complying with ANSI
A136.1) (Not to be used in exterior
applications).
• For Exterior applications, follow
stone and mortar manufacturers
recommendations.
2 | Tape
• 2 in wide high-strength
alkali-resistant glass fiber tape.
3 | Fasteners
For floors and walls:
• Minimum 1-1/4 in (for interior)
& 1-3/4 in (exterior walls) long
corrosion-resistant roofing nails.
• Minimum 1-1/4 in (for Interior) &
1-3/4 in (exterior walls) long No. 8 x
0.375 in HD self-drilling corrosion-
resistant ribbed waferhead screws.
• If compliance with ANSI A108.11
is not required, minimum 1 in long
No. 8 x 0.323 in HD self-drilling
corrosion-resistant ribbed buglehead
screws may be used for floors.
SILICA WARNING: Refer to the product Safety Data
Sheet before use. Do not handle until all safety
precautions have been read and understood. Do not
breathe dust from the product Do not eat, drink or
smoke when using this product.
The hazard associated with fiber cement arises from
crystalline silica present in the dust generated by
activities such as cutting, rebating, drilling, routing,
sawing, crushing, or otherwise abrading fiber cement,
and when cleaning up, disposing of or moving the
dust. When doing any of these activities in a manner
that generates dust: (1) comply with the OSHA PEL for
silica dust and/or other applicable law, (2) follow James
Hardie instructions and best practices to reduce or
limit the release of dust; (3) warn others in the area
to avoid the dust; (4) when using mechanical saw or
high speed cutting tools, work outdoors and use dust
collection equipment; and (5) if no other dust controls
are available, wear a dust mask or respirator that meets
NIOSH requirements (e.g. N-95 dust mask). During
clean-up, use a well maintained vacuum and filter
appropriate for capturing fine (respirable) dust or use
wet clean-up methods - never dry sweep.
BK050905
• If applying HardieBacker 500 cement
board over gypsum, use minimum 1-3/4
in long corrosion-resistant roofing nails.
For countertops:
• Minimum 3/4 in long corrosion-resistant
roofing nails.
• Minimum 3/4 in long ribbed counter
sinking corrosion-resistant screws.
• 18-gauge corrosion-resistant polymer
coated 3/4 in staples with a 1/4 in
crown.
• For HardieBacker 500 cement board,
use minimum 1-1/4 in long corrosion-
resistant roofing nails or ribbed
countersinking screws.
For vinyl and resilient flooring: (Interior Only)
• 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 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.
HardieBacker board delivers
more compressive and
flexural strength than any
board on the market.