Outdoor Cube Saunas

Why Choose a Cube Sauna?

Most people shopping for an outdoor sauna are deciding between three shapes: barrel, pod, and cube. Each has trade-offs, but the cube design wins on interior space — and it's not close.

Barrel saunas have curved walls that eat into shoulder room and bench width. Pod saunas are compact and efficient but limiting for taller users. A cube sauna gives you straight walls, a flat floor, and a full-height interior from wall to wall. That means more headroom on upper benches, wider seating, and room for two-tier layouts that actually let multiple people sit comfortably at different heat levels.

The other big advantage is aesthetics. Cube saunas look like modern architecture — clean lines, large glass panels, and a profile that fits contemporary backyards without looking like a storage shed. If the design of your outdoor space matters to you, this is the shape that earns its place visually. For a deeper look at how shapes compare, read our detailed shape comparison.

The SaunaLife Cube Series

Every cube sauna in this collection is built by SaunaLife, a manufacturer that specializes in outdoor sauna kits with Scandinavian-inspired design and thermally modified wood construction. The Cube Series currently includes five models:

• CL3G (2-Person): The entry point. A 53" x 49" footprint makes it the most compact cube on the market — ideal for solo use or couples with limited patio space.
• CL4G (3-Person): Same modern design, slightly larger interior with room for a third seat. The most popular model for homeowners who want a personal sauna without a massive footprint.
• CL5G (4-Person): Steps up to a roomier cabin with wider benches. Comfortable for two adults to stretch out or four to sit together.
• CL7G (6-Person): The social model. Two-tier bench layout lets users choose between intense upper-bench heat and a milder lower seat — great for households where not everyone wants the same temperature.
• CL12GCP (8-Person with Changing Room): The flagship. A separate changing room means you can store towels, robes, and accessories outside the sauna cabin. This is the model for families and anyone who entertains.

All five share the same design DNA: full-glass front wall, thermo-treated wood inside and out, stainless steel hardware, and pre-assembled wall panels that simplify the build. Browse the full SaunaLife collection if you're also considering their barrel or pod models.

Materials: What "Thermo-Treated" Actually Means

SaunaLife's Cube Series uses two types of thermally modified wood — and the distinction matters more than most retailers explain.

The exterior is thermo-spruce: Nordic spruce that's been heated to over 400°F in a controlled, oxygen-free process. This fundamentally changes the wood's cell structure, making it significantly more resistant to moisture, rot, and insect damage than untreated softwoods. It's the same technology used in Scandinavian building facades designed to last decades outdoors without chemical treatment.

The interior benches and walls use thermo-aspen, chosen for a different reason entirely: it stays cool to the touch even at full sauna temperature. Where untreated pine or hemlock can feel uncomfortably hot against bare skin at 180°F+, thermo-aspen has lower thermal conductivity — meaning you can sit and lean back without flinching. It's also splinter-free after the thermal treatment process.

The full-glass front wall on every Cube model isn't just aesthetic. Tempered safety glass floods the interior with natural light and gives you a view of your backyard during sessions — a noticeable psychological difference compared to sitting in a fully enclosed wooden box. If glass-front sauna designs are important to you, the Cube Series is purpose-built for that experience.

Choosing the Right Size

The right cube sauna depends on how you plan to use it — not just how many people might fit inside.

For daily solo use, the CL3G or CL4G are the practical choice. They heat up faster (less air volume), use less electricity, and take up a footprint smaller than a standard garden shed. If you're the type who wants a 20-minute session after work without a production, these are built for that routine.

For couples or regular use with a partner, the CL5G is the sweet spot. It gives both people room to sit without being elbow-to-elbow, with bench space to lie down if you prefer a horizontal session.

For families or entertaining, the CL7G or CL12GCP makes sense. The two-tier bench layout in the CL7G gives heat-level options within the same session, while the CL12GCP's changing room adds a practical layer that most outdoor sauna owners wish they'd thought of sooner — somewhere to leave clothes, towels, and shoes that isn't the ground.

Heaters and Heat Performance

Cube saunas are designed for traditional sauna heat — high temperature, low humidity, with the option to throw water on stones for steam (löyly). The heater you pair with your cube determines the experience.

For most buyers, a modern electric sauna heater in the 6–9kW range is the right match. Electric heaters offer precise temperature control, faster heat-up times, and require only a dedicated electrical circuit — no chimney, no fuel storage, no ash cleanup.

If you want an off-grid setup or prefer the ritual of building a fire, wood-burning sauna stoves are compatible with the larger Cube models (CL5G and up). Wood-fired heat feels different — a softer, more radiant warmth with the crackle and scent of burning wood that many traditionalists prefer.

Setting Up Your Outdoor Cube Sauna

Installation breaks down into three steps: foundation, assembly, and electrical.

Foundation: A cube sauna needs a flat, level, solid base. A 4-inch concrete pad is the gold standard. Crushed gravel (4–6 inches deep, compacted) works well and allows natural drainage. A reinforced deck can work too, but confirm it supports the loaded weight of the sauna plus occupants. An uneven base will cause door alignment issues and gaps between panels — this is the one step you don't want to shortcut.

Assembly: SaunaLife Cube kits arrive with pre-assembled wall and roof panels. Two people can typically complete the build in a weekend. All hardware is included, and the tongue-and-groove panel system doesn't require specialized tools. It's a substantial project, but it's designed to be a rewarding one — not a frustrating one.

Electrical: If you're using an electric heater (most buyers are), you'll need a dedicated circuit installed by a licensed electrician. The specific requirements depend on your heater's wattage and voltage. Read our electrical requirements guide for the full breakdown before you buy, so there are no surprises.

For a complete overview of everything involved in putting an outdoor sauna on your property — permits, placement, drainage, and more — our step-by-step planning and installation guide covers it all.

Not sure which shape is right for you? Browse our full outdoor sauna collection to compare cube, barrel, pod, and cabin styles side by side.