How to install WPC Decking

It is strictly prohibited to use hollow decking that’s been cut diagonally or parallel to the board as it does not hold as much load as when it’s cut at a 90 degree angle, please use solid decking if it needed to be cut diagonally or parallel to the board.

Storage & Handling

Please note that boards must always be stacked, piled and placed on a flat surface or on a close boarded, full length pallet with bearer centers of 500mm or less. Where joists are being used in stacking, support joists should be placed perpendicular to the WPC products and these boards must also be supported on a level plane. No more than 100mm of the WPC product should be overhanging unsupported. Please avoid dragging and pulling when transferring the boards, as this may damage or scratch their surfaces. If boards are to be stored outdoor over a long period of time, they should be stored in a cool dry area away from sunlight.

 

Structural

Senlue WPC outdoor decking boards are not advised for use as professional structural construction materials, and should not be used in place of: building frame, building planks or components of other load-bearing products.

Ventilation

Senlue products CANNOT be directly installed onto a flat surface. It must be installed onto a substructure, so there is adequate and unobstructed air flow under the decking to prevent excessive water absorption. A minimum of 20mm of continuous net free area under the decking surface is required for adequate ventilation on all decking so air can circulate between adjacent members to promote drainage and drying.

Fastening

When fastening Senlue clips, all screws should always be drilled onto the centre solid part of the joist at a 90 degree angle to achieve a maximum grip

All fasteners should be on their own independent joists, there must be a sister joist where the end of two boards meet. The end of each board must be fastened on its own joist with separate clips.

Spacing

Gapping rules are required when installing Senlue decking:

Type of Gap
	Above 4.5°C	Below 4.5°C
Width-to- Width	6mm	10mm
End-to-End	4mm	5mm
End-to-Width	3mm	5mm
Abutting Solid Objects	6mm	13mm

 

Step by Step Installation Guide:

 

1- Make sure the surface where you are going to layer the joists and decking is completely leveled;

2- Calculate the decking span, that is, how far apart your joists will be. Adequate spacing of the joists is required to keep the deck boards from bending. Please refer to the below charts for spacing required;

 

Maximum Decking Span (Centre-to-Centre of joist)
Product	Residential	Public Area
DE 115-19 SH 115*19 single-surfaced hollow decking	250mm	n/a
DE 145*21 RH 145-21 single-surfaced hollow decking	200mm	n/a
All other hollow decking models	300-350mm	n/a
All other solid decking models	350mm	300mm

 

Joist Spanning with Angled Decking Installation (Centre-to-Centre of Decking)
Angle	Spacing
90	Refer to the above table
60	50mm less than the above table
45	100mm less than the above table
30	1/2 distance as the above table

For applications in public area it is recommended to consult local building code official for specific requirements.

 

3- When installing your WPC, the first and the last board of your project will need to use a start/end clip. All other board will require our hidden fastener for this installation.

 

Start/end clip installation:

a) Fix the starting clip onto the joist as shown below:

B) Take your first board and push it into the starting clip as shown below:

4) Slide all clips into the grooves of the boards;

5) Fasten all clips from above by drilling screws into the middle of the joist;

6) Place the next board by pushing it in;

7) Seal the edges with skirting/end caps.

7.1) Skirting Installation

The distance between the screws must be equal to or less than 300mm and two screws must be used at each section.

 

7.2) End Cap installation

Place the end caps in front of the holes of the hollow boards and push in.