UPM ProFi

3. Substructure

3.1 To prevent movement of the deck during its lifetime, UPM ProFi Decking must always be installed on a rigid substructure frame.

3.2 Different sub-structure options exist depending on the deck design. The frame itself must be installed on a well draining hard load bearing surface e.g. concrete blocks, impacted stones, or concrete.

3.3 No matter what length, each deck board must be supported by at least three joists/support rails. Double joists/support rails (spaced 40 mm apart) must be installed at points where the ends of two deck boards meet.

 
 
 

3.4 Ground level decks

UPM ProFi Support Rail or UPM ProFi Alu Support Rail Small (if deck height is restricted) may be used when installing directly onto the ground: they may not be used for raised decks. To correct slight unevenness’s in the ground, UPM ProFi Rubber Pads may be used under UPM ProFi Support Rail only if the max distance of rubber pads does not exceed 30 cm (center to center). With UPM ProFi Support Rail and UPM ProFi Alu Support Rail Small, the rigid substructure frame must be made by fixing the support rails / joists to the ground at no more than 1m intervals. (e.g. fixing with bolts into the concrete).

 
 

3.5 Raised decks

UPM ProFi Alu Support Rail Large or suitable timber joists (eg dried hardwood durability class 1) may be used for raised decks. They may be installed on eg UPM ProFi Feet or concrete blocks. An inter-locked rigid sub-structure frame must be made by screwing together the support rails / joists and the cross members with angle brackets. The distance between cross-members must not exceed 2 m (centre to centre).

If allowed by local conditions, counter-battens can be installed as an alternative to cross member installation. They should be installed in 90° underneath the joists and fixed to them by screwing.

 
Sub-structure created of UPM ProFi Support Rails.
An inter-locked rigid sub-structure frame must be made by screwing together the support rails / joists and the cross members with angle brackets.
Raised deck with UPM ProFi Click System.
Alu Support Rail Large or suitable timber joists may be used for raised decks
Alu Support Rail Large and feet used for rigid, raised sub-structure.
If allowed by local conditions, counter-battens can be installed as an alternative to cross member installation. They should be installed in 90° underneath the joists and fixed to them by screwing.
 
 

3.6 UPM ProFi deck boards must not be used above ground level installations, unless built on a solid load bearing surface: e.g. a concrete balcony or roof terrace. 

See installation instructions for roof terraces

3.7 Joist Spacing

Due to the different mechanical properties of the different decking boards, the max joist span as described in table below must be kept. Failure to do so may result in board distortion. When laying the boards diagonally to the joists, the spacing has to be reduced by 10 cm.

 
 
The space between support rails is measured from the center to center.
Please make sure the joist spacing is correct for the decking product you are using.
 
 
The joist spacing for Piazza Pro is 40 cm in residential sites and 30 cm in commercial sites.
Piazza One is intended for residential purposes only and its joist spacing is max 35 cm.
The joist spacing for Deck 150 is max 40 cm in both residential and commercial applications.
 
 

3.8 Joist Overhang

For Piazza Pro and Deck 150 the maximum recommended overhang of a board end is 50 mm, and 30 mm at maximum for Piazza One and Terra 127.

3.9 Frame Edge with Alu Support Rail Large & Feet

A special edge construction is needed when the frame is built on feet, so that UPM ProFi Piazza One deck ends can be fixed flush with 3 cm overhang or to install UPM ProFi Rail Step. Short cross members (~60 cm) should be installed underneath the main support rails at angle of 90°. The cross members should be connected to the main support rails by screws and the outer end should be installed on a foot. The final edge support rail can then be installed on the cross members so that it is flush with the bottom of the feet. This should be made part of the rigid frame by the use of angle brackets.

See section 2 in UPM ProFi Decking Installation Images

 
Go back to installation front page
Step 4