Use and Care Guide

25
Can DensShield
®
Tile Backer
be used in floor applications?
Yes. Both
1
⁄49 (6.4 mm) and
1
⁄29 (12.7 mm)
DensShield
®
Tile Backer can be used in floor
applications. Both of these thicknesses passed
the Robinson Floor Test, the industry standard
floor test for residential and light commercial
ratings. The Robinson Floor Test (ASTM C627)
is designed to determine how a tile assembly
holds up under extreme wear and weight
conditions. DensShield Tile Backer achieves the same light commercial
rating as cement and fiber cement backers.
26
DensShield Tile Backer seems softer than cement boards.
Does it have the same floor ratings?
DensShield Tile Backer is rated for residential and light commercial floors.
1
⁄49 (6.4 mm)
DensShield Tile Backer panels have a compressive strength of approximately 1200-1500 lbs
psi, and
1
⁄29 (12.7 mm) DensShield Tile Backer has a compressive strength of between
450 and 600 lbs psi. That means that it would typically take a load of 450 to 600 lbs psi
to start to crush
1
⁄29 (12.7 mm) DensShield Tile Backer. When a load is applied to the
floor tile, the tile distributes the load over its entire area.
27
Is DensShield
®
Tile Backer installed any differently than other tile backers
in flooring applications?
No. DensShield Tile Backer in either the
1
⁄49 (6.4 mm) or
1
⁄29 (12.7 mm) thickness is installed the same way,
following the guidelines below:
• Laminate DensShield Tile Backer panels, grey coated side up, to
5
⁄89 (15.9 mm) minimum APA exterior
grade plywood subfloor or
3
⁄4 9 (19 mm) OSB using a latex portland cement mortar (complying with ANSI
A118.4) liberally applied with a
1
⁄49 (6.4 mm) square notched trowel. This is the same recommendation
as Tile Council of North America (TCNA).
• Embed DensShield Tile Backer into mortar while still pliant (do not exceed open time). Stagger DensShield
Tile Backer joints from subfloor joints; fasten with 1
1
⁄49 (32 mm) galvanized roofing nails or corrosion-
resistant screws. Avoid driving fasteners into the joists to avoid nail pops. Space fasteners no greater than
89 (203 mm) o.c. in both directions. Drive fasteners flush with the surface
— do not countersink. Apply 29
(51 mm) fiberglass mesh tape over joints and embed with latex portland cement mortar.
• Staples: (
1
⁄49 [6.4 mm] DensShield Tile Backer only)
1
⁄49 (6.4 mm) or larger crown corrosive resistant chisel-
point staples equal to approximately the total thickness of underlayment and subfloor. Staples shall be
placed 29 (51 mm) o.c. around the perimeter and 49 (102 mm) o.c. in the field ensuring that the staples
are between
3
⁄89 (3 mm) and
1
⁄29 (12.7 mm) from ends and edges.
• Apply flooring grade ceramic tile with latex portland cement mortar (ANSI A118.4). Tile must be a minimum
size of 29 x 29 (51 mm x 51 mm) or larger. Full thickness thresholds should be used, butted against the
edge of DensShield Tile Backer panels and flush with the tile surface.
• Use latex portland cement floor grout (ANSI A118.6).
• PRIOR to tile installation, all backer boards need to be protected from very heavy loads and construction
traffic such as moving appliances. Protection such as plywood should be laid down in these areas.
The drawing above
depicts how a load is
distributed over the
surface of a tile and
carried by DensShield
Tile Backer. With a
minimum tile size of
29 x 29 (51 mm x 51 mm)
a load of over 1800 lbs.
(816 kg) is needed to
overcome the compressive
strength of DensShield
and floor assembly.
Concentrated
Load
Tiles
Mortar
DensShield
Tiles
DensShield
®
Tile Backer
Floor Joists 169 (406 mm) o.c.
Base Minimum
5
⁄89
(15.9 mm)Plywood
Latex Portland Cement Mortar per ANSI A118.7
DENSSHIELD Questions & Answers 11