The interior design of Ring Spa in Tallinn was crafted by experienced interior architects Merlin Tiivel and Gertruth Alas. The project was anchored in the motif of circles, which is reflected in the spa center's name and is evident in both the interior and decorative elements. Inspiration was drawn from lush rainforests and natural materials, resulting in a comfortable, thoughtful and well-lit environment.

Architecturally, the project was influenced by the building's glass facade, creating openness and brightness. The designers aimed to create a building that seamlessly integrates multiple functions, including spa and sauna facilities, catering, accommodation, sports center and courts. The goal was to ensure a logical and cohesive spatial layout. The second-floor spa area and sauna center were given a distinctive appearance, with each sauna featuring its own unique design.