Löyly: Contemporary Sauna Architecture on Helsinki's Shore

Introduction: A New Silhouette on the Baltic

On a rocky promontory in Helsinki's southern district of Hernesaari, a dark, faceted mass rises from the shore like a piece of driftwood sculpted by wind and salt. This is Löyly, a public sauna and restaurant completed in 2016 by the Finnish firm Avanto Architects. Its name—Finnish for the steam that rises when water hits hot stones—signals a deep commitment to the rituals of Finnish bathing. But Löyly is more than a sauna; it is an urban landscape, a public space, and a striking example of how contemporary architecture can reinterpret tradition while engaging with its natural surroundings.

Hernesaari was once a shipyard and industrial area, now transformed into a residential and leisure district. The site itself is a former container port, flat and exposed, with sweeping views over the Baltic Sea toward the islands of the archipelago. Avanto's design responds to this exposure by creating a low, undulating structure that seems to grow out of the bedrock. The building's form is both monumental and soft, its silhouette echoing the gentle waves and rocky contours of the coastline.

The Architecture: A Landscape of Timber and Light

Löyly is constructed from two primary materials: a steel frame and a skin of timber. The exterior is clad in kiln-dried spruce that has been charred using the Japanese technique of shou sugi ban, giving it a deep, matte black finish. This charring not only protects the wood from the harsh Nordic climate but also lends the building a timeless, almost prehistoric quality. The black mass is punctuated by vertical fins and slats that create a rhythmic pattern, breaking down the scale and allowing light to filter through.

Inside, the contrast is striking. The interior spaces are lined with pale, untreated pine, which glows warmly in the soft daylight that enters through strategically placed glazing. This juxtaposition of charred exterior and pale interior is a deliberate play on the duality of the sauna experience—the intense heat and darkness of the steam room, followed by the cool, bright relief of the outdoors. The architects have described the building as a "landscape" rather than a "building," and indeed, its stepped terraces and gentle slopes invite visitors to climb and explore.

The main volume houses two saunas—one traditional smoke sauna and one continuously heated sauna—along with a restaurant and lounge. The saunas open directly onto a large outdoor terrace with a swimming area and a gap in the structure that allows bathers to plunge into the sea. The roof, which is accessible to the public, becomes a viewing platform and a place to sunbathe, offering panoramic views of the city and the water.

Integration with the Shoreline: A New Public Space

One of Löyly's most significant achievements is its seamless integration with the shoreline. Rather than turning its back on the water, the building embraces it, creating a series of outdoor spaces that are as important as the interior. The terraced wooden decking extends outward, forming a natural amphitheater facing the sea. This deck is not just a functional space for bathers but also a public promenade, open to all, whether they come to use the sauna or simply to enjoy the view.

This openness is a departure from the traditional Finnish sauna, which is often a private, introverted space. Löyly reimagines the sauna as a social and communal destination, a place where people gather not only to bathe but to eat, drink, and linger. The restaurant, which serves modern Finnish cuisine, is integrated into the building's flow, with large windows that connect diners to the surrounding landscape. The result is a building that is both a cultural institution and a leisure facility, a place where the ritual of the sauna is made accessible to a wider public.

Finnish Bathing Culture: From Tradition to Destination

The sauna has been a central part of Finnish culture for thousands of years, traditionally a place for cleansing, healing, and social bonding. In rural Finland, saunas were often the first building erected on a new homestead, and they served as a place for childbirth, washing the dead, and even curing meat. Today, the sauna remains a cherished ritual, but its role has evolved. Löyly represents a modern interpretation of this tradition, one that emphasizes the social and recreational aspects of bathing while honoring its roots.

Avanto Architects, led by Ville Hara and Anu Puustinen, have been at the forefront of this reinterpretation. Their design for Löyly was born out of a competition held by the City of Helsinki to create a public sauna that would revitalize the Hernesaari waterfront. The architects drew inspiration from the Finnish concept of "everyman's right," which allows everyone to access nature, and they sought to create a building that would be open and welcoming to all. The result is a sauna that is as much about the experience of the landscape as it is about the heat and steam.

The building's success has made it a destination in its own right, attracting both locals and tourists. It has been featured in numerous international publications and has won several awards, including the 2017 Finnish Wood Prize. More importantly, it has sparked a revival of public saunas in Helsinki, with new ones opening in other parts of the city. Löyly has shown that the sauna can be a contemporary architectural typology, capable of responding to urban contexts and creating vibrant public spaces.

Materiality and Craft: The Role of Wood

Wood is the soul of Löyly, and its use is both practical and symbolic. Finland is a country of forests, and timber has long been a primary building material. However, modern construction has often favored concrete and steel. Avanto's decision to use wood for the entire structure, including the load-bearing frame, is a bold statement about sustainability and craftsmanship. The charred exterior, in particular, is a testament to the durability of wood when treated properly. The shou sugi ban technique, which originated in Japan, involves burning the surface of the wood to create a layer of charcoal that is resistant to moisture, insects, and fire. This method not only extends the life of the timber but also gives it a rich, tactile quality that changes with the light.

The interior's pale pine, in contrast, is left untreated, allowing the natural grain and color to show. Over time, the wood will darken and develop a patina from use and humidity, adding to the building's sense of history. This use of raw, natural materials creates a strong connection to the environment and a feeling of authenticity that is often lacking in contemporary architecture.

A Place for All Seasons

Löyly is designed to be experienced in all seasons, and its relationship to the weather is a key aspect of its design. In the summer, the outdoor terraces and swimming area are in full use, and the building opens up to the sun and sea. In the winter, the contrast between the hot sauna and the cold air is invigorating, and the charred exterior stands out against the snow. The building's low profile and dark color help it absorb heat from the sun, while the large windows maximize natural light during the short days.

The architects have also considered the microclimate of the site. The terraces are oriented to catch the prevailing winds, which help to cool bathers after a hot sauna, and the building's form provides shelter from the harshest weather. This attention to environmental comfort makes Löyly a comfortable place to be year-round, encouraging visitors to engage with the outdoors even in the depths of winter.

Conclusion: Why Löyly Still Matters

Löyly is more than just a beautiful building; it is a model for how architecture can enhance public life and connect people to their environment. In an era of increasing urbanization and digital distraction, it offers a space for physical and mental well-being, rooted in centuries-old traditions. It demonstrates that contemporary design can be both innovative and respectful of the past, and that sustainability is not just about technology but about using materials and forms that are in harmony with the landscape.

Its legacy lies in its ability to make the sauna accessible to everyone, breaking down barriers of class and culture. It has become a symbol of Helsinki's transformation from a port city to a cultural capital, and it continues to inspire architects and city planners around the world. As we face the challenges of climate change and social isolation, Löyly reminds us of the importance of public spaces that bring people together and foster a sense of community. It is a testament to the power of architecture to create places that are both functional and poetic, and it will remain a landmark on Helsinki's shore for generations to come.