The choice of designers is based on a public competitive tendering process complying with the Act on public purchases. There are five contracts on architectural design, two on rock engineering design, one on geotechnical engineering design, one on track engineering design, one on structural engineering design and four on technical building services design.
Architectural design:
Innovarch Architects (tunnel)
HKP Architects (Matinkylä and Jousenpuisto stations, Niittykumpu station option)
Arkkitehtityöhuone Artto Palo Rossi Tikka Architects (Tapiola station)
Consultants consortium ALA Architects Ltd & Architects Esa Piironen Oy (Otaniemi and Keilaniemi stations)
Helin & Co Architects (Koivusaari and Lauttasaari stations)
Geotechnical engineering:
Consultants consortium FKW
Track engineering:
Consultants consortium FKW
Rock engineering:
Consultants consortium FKW between Ruoholahti and Keilaniemi
Consultants consortium Sito-Pöyry-Fundatec between Keilaniemi and Matinkylä.
Structural engineering:
Insinööritoimisto A-Insinöörit Oy
Technical building services:
Pöyry Building Services Oy (HVAC, electrical works and automation for tunnels and shafts)
Insinööritoimisto Olof Granlund Oy (HVAC for stations)
Consultants team Nissinen-Niemistö (electrical works and automation for stations).