How to Design a Custom Sauna for Your Home or Lodge

A space shaped by ritual

Designing a sauna is not simply a question of where it will fit, but of how it will feel. The process begins long before materials are chosen or drawings are made. It begins with an understanding of rhythm: the slow transition from heat to cold, from noise to silence, from doing to being.

A well-designed sauna is a space built for ritual. It must respond to the body and the landscape, offering both heat and stillness. For some, it becomes a private retreat at home. For others, it anchors a lodge or guesthouse, offering guests a quiet moment of recovery.

Every custom sauna reflects its place, its purpose, and the care of those who built it.

Understanding how a sauna works

At its simplest, a sauna is a room heated to between 70 and 100 degrees. But good design turns that temperature into an experience. The success of a sauna lies in its balance: between materials that hold warmth and those that breathe, between enclosed heat and connection to air, between privacy and view.

The ritual follows a rhythm of time in heat, a plunge into cold water, then rest. The sequence repeats until the body settles into calm. The building must support that flow, guiding the user through the experience without effort or interruption.

Designing a sauna well means thinking like both builder and user. Every material, joint, and window has purpose.

Starting with place

The best saunas feel as though they belong to their setting. In New Zealand, where landscapes shift quickly from coast to bush to alpine, the design should be led by what surrounds it.

A clifftop sauna overlooking the ocean may face west to capture the evening light, while one in alpine snow might use small windows to retain heat. A bush sauna could open discreetly to filtered sunlight through native trees.

The landscape provides not just a view but an atmosphere. The way the light moves, the sound of water nearby, and the direction of prevailing wind all inform how the structure should sit.

A sauna that belongs to its place does not compete with its environment. It complements it.

Timber as structure

In most modern construction, walls are layers of framing, insulation, cladding, and lining. A log sauna is different. Its structure and surface are one and the same.

At Heritage, each sauna is built from solid interlocking New Zealand Redwood logs. The timber forms both interior and exterior walls, connected with dovetail joins that hold without screws or nails. Over time, the logs settle and tighten into place.

This kind of construction gives a sauna its permanence. It also defines its atmosphere. The thickness of the timber creates natural insulation, holding heat gently rather than trapping it. Inside, the scent of warm wood adds another layer of calm.

When designing a custom sauna, the timber is not just a material but a presence. Its grain, tone, and texture shape how the space feels before any heat is added.

Considering heat and heart

The stove is the centre of the sauna, both physically and emotionally. Whether wood-fired or electric, it determines how the heat builds, how it radiates, and how the ritual unfolds.

A wood-burning stove offers the most traditional experience. The sound of fire, the rhythm of adding wood, and the glow of embers create a sensory connection that cannot be replicated. In rural settings or lodges where firewood is plentiful, it makes perfect sense.

In urban or remote contexts, an electric stove provides ease and consistency, maintaining temperature with precision. The choice depends on the balance of ritual and practicality that suits the space.

What matters most is placement. The stove should feel central, not as a feature but as a quiet heart. Benches and space flow outward from its warmth.

Designing the ritual flow

A sauna is not an isolated room; it is part of a sequence. When designing a custom sauna, think beyond the interior. The entry, the cool-down area, and the route to water all form part of the experience.

Ideally, a sauna connects directly to an outdoor space such as a cold shower, plunge pool, or simply a place to step into fresh air. The movement from heat to cold to rest should feel effortless.

In lodges, this might mean a short walk across timber decking toward a natural pool or spa. At home, it could be a shower set discreetly beside the structure. What matters is that the ritual continues beyond the walls.

Light and view

Light changes everything. In a sauna, it needs to be present but controlled. Natural light creates warmth and depth, but too much can disturb the sense of enclosure.

Small, strategically placed windows allow users to connect with the landscape while maintaining privacy. A view of water, sky, or trees anchors the experience in its surroundings. Even a narrow slit of glass can provide orientation and calm.

Artificial lighting should be minimal and warm. Hidden fixtures that wash light gently over timber create atmosphere without distraction.

Good lighting design makes a sauna feel alive, shifting subtly through the day and night.

Crafting the interior

The interior of a log sauna should feel honest. The same timber that forms the structure defines the inside. Benches are designed for comfort and proportion, allowing heat to circulate evenly.

Each surface is touched directly, so craftsmanship matters. Edges are softened, joins are precise, and finishes are breathable. No synthetic coatings or unnecessary details.

A custom sauna can also reflect its owner’s rhythm. Some prefer a simple single-level bench for meditative heat, while others opt for multiple tiers to vary intensity. Handles, backrests, and windows can be positioned to match the way the space will truly be used.

The beauty of a custom build lies in its precision, not in ornament, but in how well it fits its purpose.

Sustainability through longevity

Designing a custom sauna is an opportunity to build with conscience. True sustainability comes from building something that endures.

New Zealand Redwood, grown and milled locally, is a renewable timber with a natural resistance to decay. Its use reduces transport impact and supports local forestry. The construction method of solid logs without insulation layers minimises materials and waste.

A well-built sauna will last for generations. It will settle, season, and darken gracefully. The most sustainable structure is the one that does not need to be replaced.

Working with an architect or designer

For lodges, retreats, and architecturally led homes, collaboration is key. Integrating a sauna into an existing design requires sensitivity to proportion, placement, and materiality.

An architect can help align the sauna with the broader rhythm of the building, ensuring sightlines, access, and orientation all feel intentional. The best collaborations are those where the sauna feels inevitable rather than added on.

At Heritage, we often describe the process as joining craftsmanship with architecture. The sauna becomes part of the architectural story, built to the same standard and philosophy as the home or lodge itself.

The luxury of permanence

In the global shift toward wellness, luxury has taken on a new meaning. It is no longer about excess or display, but about time, space, and permanence. A custom-built sauna embodies all three.

It is a place to step away from urgency. It holds its warmth quietly. It is made to last.

For homeowners, it becomes a private retreat, a few steps from the main house but a world apart. For lodge owners, it offers guests an experience that defines their stay. For both, it is an investment in calm that only grows richer with age.

A structure to keep

The process of designing a custom sauna is, in itself, a kind of ritual. Each decision, from timber selection to the cut of a dovetail joint, contributes to an object that is both architectural and personal.

Unlike prefabricated panels or kit saunas, a handcrafted log sauna is built to stay. It becomes part of its landscape and, over time, part of its owner’s routine.

To design one is to consider not just how it will look when new, but how it will feel in twenty years, when the timber has deepened, the stove has seasoned, and the building has settled fully into its place.

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A sauna is more than a room of heat. It is a rhythm of design and experience, a structure that restores as much as it shelters.

To design one well is to think not only of warmth and comfort, but of craft, sustainability, and permanence. It is an act of building for calm, something that will serve quietly for generations.

Whether placed beside a lodge, tucked into a coastal garden, or built among trees, a custom sauna becomes a statement of what we value most: time, care, and the enduring strength of timber.

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