4. Preparing to install the deck boards

4.1 Inspection & cutting to length

Before installing the deck boards it is important to check for possible colour variations between different batches. If they exist, it is best to mix the different batches together. If in doubt please contact your local dealer before installing.

4.2 As the boards are cut to length while still moving in the production process, to ensure perfect square ends and exact length requirements, it is recommended to trim the board ends before installation. It is important that the boards are cut at approximately the same temperature, otherwise the lengths will vary slightly when the temperature equalizes. Deck board end trimming at the edge of the deck is best done after installation using a circular saw with guide rail. For perfect finishes we recommend to chamfer the cut edges of the boards.

4.3 Before installation, the ends of UPM ProFi Piazza One deck boards may rise slightly. This has no effect on the deck properties and the boards automatically become flat again with installation on the rigid sub construction frame.

4.4 The boards can be cut and shaped in the same way and with the same tools as for timber decking.


4.5 T-Clips, Wing Clips & Alu Rail

The design of UPM ProFi deck boards enables installation with UPM ProFi clips or alu-rails, avoiding unsightly screw heads on the surface of the boards. Both methods allow the natural thermal movement of the boards and create a gap of 6 mm between the board widths. Both systems also allow the de-installation of single boards if needed. UPM ProFi Alu Rails provide a closed surface which prevents leaves, food or other items falling through. In the case of Deck 150, the Alu Rail also strengthens the board edges and provides a stronger structure for commercial and hot country applications. Additional ventilation points are needed when installing with Alu Rail. (see 2.3). The following table shows which clips and alu-rails should be used with which boards.


4.6 Screws

It is important to use the correct screws. Use of other screws may lead to product failure and could invalidate the manufacturer’s guarantee. Low-quality screws may cause stains on the deck.  

Start Clips & direct fixing on UPM ProFi Alu Support Rail Large or Small

  • UPM ProFi A2 3.9x22 mm stainless steel screws (available separately from Start Clips)

T-Clips, Wing Clips & Alu Rail on UPM ProFi Alu Support Rail Large & Small

  • UPM ProFi A4 4x26 mm stainless steel screws (included in special T-Clip & Wing Clip for Alu Support Rail boxes and available separately for Alu Rail)

4.7 The correct torque and tool speed (max. 500 RPM) should be used to ensure the screw head finishes level with the clip surface. Do not insert the screw too deep into the clip.


See section 3 in UPM ProFi Decking Installation Images