The lower ceiling of the expanded Terminal 2 of Helsinki-Vantaa Airport is a proud achievement of Finnish wood design and construction, and it has been awarded the International Wood Architecture Award 2022. In order to preserve this award-winning design in the best possible way for many years, both the interior and exterior wooden ceilings have been coated Technology AQUATOP 2600-90 translucent matte topcoat.

When describing the winner, the award judges praised the design for its ambition and professional conception and commented “visually, the roof is uniform thanks to the uncompromising finish and smooth surface treatment” (Puuupalpito, Puuinfo). They also recognized the calming effect of wood and its use as a building material in the hectic environment of the airport.

Challenging wooden structure

The wood produced by Raision Puusepät Oy was used for the roof of the departure hall, the outer box and around the skylight of the terminal for a total of 7700 m². The undulating shape of the roof is made of thousands of curved wooden elements and was one of Raisio Puusepi’s most challenging tasks.

“We started planning the project at an early stage and also made additional investments, such as a new CNC milling machine,” says Jari Saarinen, Raisio’s carpentry production manager.

“The production of the elements started about a year before the opening of the terminal. The first element was lifted into place in August 2021. All in all, we have produced more than 10,000 different parts for this site,” continued Saarinen.

Uniform quality in wood materials and coatings to thousands of parts

All elements were manufactured in Raisio’s own carpentry facilities, the largest of which are over 6 meters long and weigh up to 1,200 kilograms.

The shape of the wooden roof is made of multi-layer wooden boards, the most visible surface of which is low-branched spruce. The wooden planks are supported on a hidden pine frame, which in turn is attached to the steel structures. The wooden boards are coated with Teknos water-based, tinted AQUATOP 2600-90 varnish.

“We use the airmix automatic spraying line and the surface treatment went without any problems. I am satisfied with Teknos’ customer service and technical support, because even though we used about 13,000 liters of paint, the product and tinting were always of uniform quality,” Saarinen emphasizes.

Based on the architect’s drawings, data models were made of all the parts of the roof, which could be fed to a CNC machine that reads 3D files. The finished parts were finished with putty and by milling edge rounds before surface treatment.

Two coats were applied with an automatic sprayer and some smaller parts were sprayed by hand. The finished elements were packed for transport in plastic that protects against the sun’s UV radiation.

“Only after the roof was installed were we able to see the result of our work in the right environment with its uniform appearance. We believe that the product we manufacture should last at least as long as its life cycle goals.” summarizes Saarinen.

High environmental awareness

The project has been built in accordance with the BREEAM (Building Research Establishment Environmental Assessment Method) environmental assessment method. Excellent environmental rating that looks at the ecology of buildings, including a requirement for very low VOC emissions in surface treatment products. Other requirements of the project team were high-quality structures, flawless finish, easy maintenance and a longer life cycle.