Accessible composite decking for a housing unit – Durable UPM ProFi replaces an old timber deck

UPM ProFi Deck 150 Pearl Grey with Click System, Helsinki, Finland

Helsinki-based organisation Lyhty ry provides housing for disabled people in the Finnish capital’s metropolitan area. The timber deck at one of the homes was reaching the end of its lifespan after a mere 15 years of use. It could no longer be used due to safety reasons. In the summer of 2019, Lyhty chose to replace the decking with a durable composite material supported by an aluminium sub-frame structure. The residents of the housing unit can now enjoy their safe, accessible and durable open-air living space.

The decking was installed by the contractor company Espoon PihanTekijät, whose certified installers have completed their Gold status UPM ProFi training.

“To make sure the decking would meet the demands of its users, all aspects of the construction—from the deck’s dimensions to its sub-frame and the decking material—were carefully thought out. The steps and their visibility had to be taken into account in determining the height of the decking. Moving wheelchairs over the edges of the decking causes a lot of wear, so durability becomes a key question,” explains Heidi Nyytäjä of Espoon PihanTekijät.

The renovation focused on accessibility and durability.

“The purchaser, an organisation providing homes for disabled people, chose to go with a composite material. The existing larch decking was out of commission due to serious rot damage issues,” describes Nyytäjä.

“The old decking had been built 15 years earlier and could not be used any longer. We wanted a material that’s both long-lasting and safe for all users. Our choice was UPM ProFi, as it’s the best material no matter how you look at it — it’s neat, aesthetic, hard-wearing and easy to clean,” says Lyhty ry’s Petri Helander.

Installation: It’s all about planning

No big surprises were encountered when installing the decking or its sub-frame. Its success hinged on good planning and a careful installation process.

“Detailed planning is half the job. You have to carefully plan where the joints and things like planters will be, and use that information to measure everything, make preliminary arrangements and build the frame,” explains PihanTekijät installer Tony.

The sturdy aluminium Click System was chosen as the deck’s sub-frame.

The ground surface was uneven, and dozens of centimetres below a desirable level. Building a timber frame under the decks would have evened out the height difference, but instead the problem was solved with foundation blocks: a rot-proof material was placed under the plastic feet of the decking. Neither the installer nor the purchaser entertained the idea of a timber frame.

The people at PihanTekijät list the greatest advantages of UPM ProFi: It doesn’t rot, the surface has good friction (not slippery even when wet) and it is low maintenance (no need to oil every year or two). Another example of this level of durability is UPM’s ProFi Click System, which is based on aluminium and plastic materials.


UPM ProFi Deck 150 Silver Green, Helsinki, Finland


  • Replacement decking for a disabled people’s housing unit in Helsinki in the summer of 2019

  • Focus areas: accessibility and durability

  • Installed by Espoon PihanTekijät Oy, whose employees have received Gold certification in UPM ProFi training

  • The product: UPM ProFi Deck 150 composite decking in Silver Green, stair decking around the edges in a Stone Grey accent

  • Sub-frame: sturdy aluminium Click System

  • Deck size: approx. 200 square metres, two separate structures