POLYUREA FOR DURABLE WATERPROOFING OF STADIUM'S WOODEN GRANDSTANDS

The wooden floor of the grandstand at the new stadium was given a durable and waterproof polyurea coating that protects the area under the stands. The building's frame structures from glued laminated timber were also treated with a wood preservative to protect them from signs of ageing and weathering.

A CHALLENGING SITE AND A TIGHT SCHEDULE

Spring 2018 marked the completion of a baseball stadium with 2,500 seats in Joensuu, Eastern Finland. The schedule of the construction project was tight because the actual construction work didn't begin until late fall. Tricky and ever-changing weather conditions added an extra layer of challenge to the project.

Besides baseball, the stadium will also host concerts. The most modern baseball stadium in Finland is an excellent reference site for all parties involved. Around seventy companies were involved in the construction of the stadium. "There aren't many timber construction sites this challenging in Finland," says Teemu Rautiainen, Construction Site Manager. 

Carefully selected coatings protect the multi-purpose stadium from ageing and weathering. The floors and stairs are up for a lot of use under the feet of the audiences and the changing Finnish weather. The pure polyurea coating makes the seating waterproof and extremely hard-wearing. 

At Teknos, even the polyurea can be tinted, allowing for the stadium's characteristically beautiful and harmonic color scheme. 

THE POLYUREA COATED ROOFING PROTECTS THE FACILITIES UNDER THE GRANDSTANDS

The pure polyurea coating was chosen for the site because of its range of benefits. Thanks to the waterproofing properties of polyurea, the facilities under the grandstands will be well protected. "Coating is one of the most significant factors in protecting the stadium from weather and wear. The grandstands function as the roof of the facilities below. The wear rate of the stands is also high because of the number of people using it," Rautiainen explains. Polyurea was also selected for the protection of the floors of the kitchen and toilet facilities of the stadium. To prevent slippage, the polyurea coating was roughened. 

The tight schedule of the project was not slowed down by the coating. Hardening in seconds, the polyurea was sprayed successfully even in the highly changing weather conditions of the Finnish spring.  "That the coating could be applied even during freezing temperatures was an absolute requisite in terms of our scheduling," says Rautiainen.

Teknos tinted the polyurea to match the color scheme of the stadium. Teknos' extensive support in the project was important, and Teknos was the only paint manufacturer able to meet the color requirements for the quantity of tinted polyurea that was needed. "Our product development chemist prepared a special batch of tinted polyurea specifically for this project," says Mikael Nurminen, the Teknos sales engineer and consultant at the construction site.

The stadium coating was a unique project also from the perspective of the coater. "The project was interesting because the grandstands are wooden. As a living material, wood brings its own challenges because the object needs to be carefully primed," explains Valtteri Lapinkangas, coating professional at Covertec Oy.

GLUED LAMINATED STRUCTURES PROTECTED FROM WEATHER

The glued laminated timber structures were primed with the AQUA PRIMER 2907 wood preservative. Finding the appropriate coating was easy because the same treatment was used for the protective treatment for the central arena next to the stadium already in 2012. 

The timber constructions of the stadium consist of glued laminated timber of up to 30 meters as well as thousands of smaller glued laminated timber pieces. Both visible and hidden pieces have been surface treated. This solution protected the wooden pieces also during construction. The treatment of timber structures of such different sizes is a lengthy process, but the coating system supplied by Teknos was praised for its short drying period. "It didn't take long to apply and to pack everything up," explains Koskenniemi.

Koskenniemi gives positive feedback for the teamwork with Teknos. "It's easy to make orders and to get in touch with the person you need. We often get projects where we need to ask for advice for picking the best treatment option, and we always get answers and color samples when needed."