Installation Guide

Page 5
TimberTech Square Shouldered Planks
Terrain, Tropical, Legacy, Twin Finish
®
, Reliaboard
®
, and Docksider
®
Important Information
To get information on other TimberTech products, visit
timbertech.com or ask your dealer for these installation guides:
• TimberTech planks are intended to be installed embossed
side up. The unembossed surface is not to be used as a
walking surface. This applies to all decking surfaces.
• The serrated bottom side of TwinFinish is great for accents
like benches and flower boxes.
• In areas with obstructed airflow such as roofs and
on-grade applications, a minimum of 1-1/2” sleeper system
supported by and connected to the substructure over which
the deck is built is required.
• To aid water run-off, the deck should slope 1/2” for every 8’
away from the house.
• To further minimize expansion and contraction, proper
ventilation and airflow should be considered.
• For best practices in climates with extreme temperature
cycles, limiting the length of the deck plank and avoiding
affixing to the rigid length of the joist in applications such as
picture framing or parting boards can help avoid movement
and screw shear.
Square Shouldered Plank Installation
Instructions
• Always be sure to check and cut the factory cut ends of all
boards to ensure they are square.
• Install from the outside edge of the deck and work toward
the house.
• Fasten no closer than 3/4” from the outside edge of each
plank, using two screws per joist including end joints.
• For gapping requirements, see page 3.
• The ends of the planks must fall on a joist. Always double
joists at butt seams. Do not toe screw deck planks as this will
cause splitting.
• Always install fasteners perpendicular to plank surface and
drive flush. Do not overdrive or splitting and mushrooming
will occur.
• Pre-drilling is required when within 1-1/2” of the ends of the
plank and for temperatures below 45 degrees Fahrenheit to
avoid end splitting and screw shear.
Special conditions will require an engineering inspection and/or
reduced spans. Always consult local building codes.
Standard Joist Spacing
90° Angle 30° Angle 45°Angle
100psf 24" 24" 24”
90° Angle 30° Angle 45° Angle
100psf 20" 18" 16"
100psf 16" 14" 12"
TwinFinish
ReliaBoard , Terrain, Legacy
DockSider
3/4”
3/4”
Directional Notch
TwinFinish, ReliaBoard, DockSider, TwinFascia and
TwinRiser Boards:
The surfaces of these products are directional in manner. A
notch has been added to one side of the planks. When installing
planks, this marked edge must be laid to the same side for the
entire installation for a consistent appearance. The TwinFascia
board has one long edge beveled on the front and back. To
ensure a consistent appearance from board to board when
installing the TwinFascia, the beveled edge must be laid to the
same side. If you rip a piece of TwinFascia be sure to note the
location of the bevel on the ripped piece to ensure consistency.
Identification
Mark
Bevel
Bevel
TOPLoc Face Fasteners are recommended for best results.
Further instructions available in TOPLoc Package.
• On-grade decks must have additional provisions for drainage
beneath the deck structure.
For best practices, decking should not be installed in
applications where ventilation and airflow cannot be achieved.