The restoration of the wood-clad exterior of the Olympic Stadium calls for accurate dimensioning and craftsmanship

The cladding of the Helsinki Olympic Stadium was rebuild by Siparila, a company renown for its woodworking skills. This national monument of historic value was restored to its original splendour as closely as possible.

In the course of the restoration, the wood cladding was modelled on the original design except that it was be extended two meters upwards to conceal the new stadium canopies.

Challenges posed by the curved inclined exterior

Structurally, the higher-than-before wooden exterior was implemented using a separate supportive lattice to which the frame and wood cladding was fixed. The biggest challenge in the project was the complex form of the exterior in which the walls tilt outward especially at the ends.

“No doubt this was the toughest project we’ve ever tackled. Special attention needed to be paid to dimensions and framework details. Even a minor deviation at a single point is multiplied as you proceed outward,” says Chief Sales Officer Olli Prättälä of Siparila explaining the challenges they were facing.

On-site safety was another challenge because the installations were carried out at elevated levels. Since it was not possible to construct scaffolding, the installers carried out their work using boom lifts and aerial work platforms. Because of safety considerations, the area underneath the platforms was off limits for other on-site workers.

Smartly new – with due respect for the old

The wood cladding of the Olympic Stadium was re-created following the original design as closely as possible. At the tendering stage, Siparila supplied a total of nine test walls of different shades and finishes which were then installed on the south end of the Olympic Stadium exposed to the action of weather for two months. The tests showed that the finish satisfied stringent quality requirements. The width of the panels supplied by Siparila was slightly adjusted to match the original.

 “It’s fair to say that this was no run-of-the-mill job, it was like walking on eggshells. The project called for true craftsmanship and forward thinking – you need to keep the subsequent work operations in mind all the time because any errors were multiplied in the course of the work,” Prättälä says.

Finnish wood

The external cladding of the Olympic Stadium consist of Finnish PEFC-certified fine-sawn spruce. The finely textured surface provides better adhesion for paint than an unfinished coarse surface, which gives it enhanced weather resistance in harsh conditions. All in all, the external cladding covers an area of 9,000 m2 with the total quantity of spruce reaching 500 m3. Theoretically, the wood cladding of the Olympic Stadium will trap up to 500 tonnes of carbon dioxide over its life cycle. The cladding panels are finished in an industrial process under controlled conditions. The final coat of paint was brush-applied to the installed cladding  as required by the painting certificate.

The Helsinki Olympic Stadium was re-opened in the summer 2020. It looks practically the same as at the end of the 1952 Olympic Games.


Additional information:

Olli Prättälä, Chief Sales Officer

Siparila Oy


+358 (0)44 3334 617


Juha Sojakka

Siparila Oy, CEO

+358 (0)44 3334 610


A family-owned company established in 2003, Siparila manufacturers claddings, interior panels, mouldings and glue-laminated boards for commercial and industrial uses. Siparila’s mission is to make life easy for builders by manufacturing completely finished painted wood products for construction and renovation. All Siparila products are made in Finland. The production facilities are located in Vaajakoski, Parkano, Kajaani and Kouvola. Siparila employs 130 woodworking professionals and its annual revenue is EUR 33 million. Siparila products are exported to Japan, Holland, Canada, the UK, Denmark, Norway, Iceland and Germany.