The sauna's curved cedar interior, sculpted into flowing ribs and low benches around a large oval window that frames open water and a distant treeline.
A portrait view of the same carved cedar chamber, a bench curling beneath one oval window while a second opening looks through to the lake.

Grotto Sauna

Perched on an island's edge in Georgian Bay, Ontario, the Grotto Sauna is a feat of old-world craftsmanship and new-world sustainability made possible by cutting-edge software and fabrication technology. It is a sculpted space, a sensual experience, and a sophisticated exercise in building science. Inspired by an Italian grotto, our design pays homage to the rugged extremities of the northern Canadian landscape. To the extent that the objective was to tell an architectural story of escape and refuge, we conceived of a design that marries contrasts to transport visitors into an otherworldly sanctum. A simple but dignified exterior built from charred cedar prepared using the traditional Japanese Shou Sugi Ban method conveys a weathered appearance; it's as if the building has been hidden in plain sight for centuries. By contrast, the warm, curved interior simultaneously emulates Lake Huron's waves and mirrors the Precambrian shield, a soft, undulating rock surface that has been worn over billions of years. The luminous glow of the interior wood enhances the sunkissed sauna experience, while the pre-aged exterior veils the intimacy of that experience from the world.

The charred cedar volume set low on a pink granite shore at dusk, its oval window facing a calm bay, with a lone windswept pine and black-eyed Susans in the foreground.

Project details

A close view of a black sauna stove filled with dark rocks, set into the pale curved cedar floor, with the lake and a wooded shoreline soft behind it.
Client
Withheld
Type
Spa, Wellness
Location
Georgian Bay
Area
800 sqft (75 sqm)
Photo Credit
Jonathan Friedman
The charred cedar box wedged into the rock at sunset, the low sun laying a bright path across the water beside its oval opening.
The prefabricated sauna slung from a crane on a barge, swinging over the water toward the granite shore during installation.
The blackened cedar exterior standing on bare granite under a heavy grey sky, the oval window cut through the wall above the water.

Awards

  • OAA Design Excellence 2015
  • WAF World Building of the Year, Shortlist 2015
  • BOYA, Best in 10: Beauty and Spa 2015
  • Architizer A+ Popular Choice Winner 2015
  • Interior Design Magazine Award, Best of 2014
  • Ontario Wood WORKS! Wood Design Award 2014
  • AIA International Honor Award 2014