SaunaLife Cube Series Buying Guide: CL3G vs CL4G vs CL5G vs CL7G

The SaunaLife Cube Series looks simple from the outside with its modern style and design, yet the the buying decision requires insight. The CL3G, CL4G, CL5G and CL7G differ in bench length, usable depth, heater choices, site demands and the way people actually fit inside. In this guide, we will outline these variations in the hopes of allowing you to make an informed decision.  

SaunaLife CL3G vs CL4G vs CL5G vs CL7G: quick comparison

If you are early in the decision, start with the footprint and the bench layout. Those two details tell you more than the person-count badge. The CL4G is the clearest example: it is almost the same width as the CL5G, but it is much shallower. That makes it a very different product even though the model numbers sit next to each other.

2 people

CL3G

Smallest footprint. Best when space efficiency matters most.

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3 people

CL4G

Wide but shallow. Strong choice when you want a long bench.

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4 people

CL5G

Same broad width as CL4G, with noticeably more interior depth.

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6 people

CL7G

Group-size model with two-sided seating and a much larger project footprint.

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*Dimensions are based on current SaunaLife product data and model-specific technical drawings. CL7G consumer listings may round depth differently; use the current drawing supplied for your project when confirming final clearances.

Browse the full SaunaLife Saunas collection if you want to compare the Cube Series with other SaunaLife formats.

Do not choose a sauna by “capacity” alone

A 2-person, 3-person, 4-person or 6-person label is useful for sorting products. It is not a comfort measurement. In a traditional sauna, the important questions are more practical: How long is the upper bench? How deep is it? Does the heater take away usable floor space? Can one person stretch out? If three people sit together, are all three on the same level?

This is where the Cube Series separates itself model by model. The CL3G is compact enough that most adults will use it mainly as a seated sauna. The CL4G changes the experience by stretching the main bench to about 76 inches while keeping exterior depth near 49 inches. The CL5G keeps that broad width but adds roughly 14 inches of exterior depth. The CL7G changes the layout again with seating on both sides of the room.

SaunaLife CL3G: the compact 2-person outdoor cube sauna

The SaunaLife CL3G is the smallest model in this comparison. Its technical drawing places the exterior at roughly 53.2 inches wide by 51.2 inches deep by 81.9 inches high, with an interior around 49.6 inches wide by 43.2 inches deep by 75.4 inches high.

The main Thermo-Aspen bench is about 49.2 inches long and 20.5 inches deep, with additional lower and side seating surfaces. That is enough room for two seated bathers, but it is not a full-length reclining bench for most adults. That distinction matters if your idea of a sauna session includes lying down.

Rated capacity2 people

Main bench length~49.2 in

Choose the CL3G if One or two people will use the sauna most of the time and keeping the backyard footprint small is more important than having a long bench.

Move up from the CL3G if You want to recline, regularly host a third person, or prefer more distance between the seating area and heater.

View CL3G Current Price & Options

SaunaLife CL4G: the wide, shallow 3-person cube sauna

The SaunaLife CL4G is one of the most interesting models in the range because its shape is not what the “3-person” label suggests. It is about 80.7 inches wide but only 49.2 inches deep. The interior is roughly 77.2 inches wide by 41.3 inches deep.

The technical drawing shows an upper bench that runs about 76 inches across the rear wall. For many users, that creates enough length to sit with legs extended or recline when using the sauna alone. Whether you can lie completely flat depends on your height and how you position yourself.

The key comparison is CL4G versus CL5G. They are almost identical in overall width, but the CL5G adds substantially more front-to-back depth. If your site is tight between a fence, patio edge, pool deck or walkway, the CL4G can preserve that long-bench feeling without taking on the deeper CL5G footprint.

Choose the CL4G if You want a modern 3-person outdoor sauna, a long rear bench and a relatively shallow footprint.

Move up to the CL5G if Three to four people will use the sauna regularly and you want more usable lower-level seating and circulation space.

View CL4G Current Price & Options

SaunaLife CL5G: the deeper 4-person outdoor cube sauna

The SaunaLife CL5G keeps the CL4G's broad 80.7-inch width but increases exterior depth to about 63 inches. Inside, depth grows to roughly 55.1 inches. That extra space is the real reason to move from CL4G to CL5G; it is not simply “one more person.”

The CL5G retains an approximately 76-inch upper bench while adding a much deeper lower seating area. SaunaLife lists the lower bench depth at about 31.1 inches and the side section at about 23.6 inches. In practice, this gives a group more places to position feet, shift seating and enter or exit without the room feeling as compressed front to back.

If the sauna is mainly for one or two people, the CL5G can still make sense if you value space over footprint. If four people will use it regularly, this is the first Cube model in the lineup where the interior starts to feel designed around group use rather than occasional extra capacity.

Choose the CL5G if Three to four regular users need more interior depth, but you do not need the CL7G's much larger group layout.

Stay with the CL4G if Two people are the normal use case and backyard depth is a bigger constraint than extra lower seating.

View CL5G Current Price & Options

SaunaLife CL7G: the 6-person Cube built around group seating

The SaunaLife CL7G is not simply a stretched CL5G. The layout changes. Its model drawing shows tiered seating on both sides of the cabin with an open central area, creating separate seating zones rather than concentrating most users along one rear bench.

The technical drawing is roughly 91 inches wide by 87.5 inches deep by 93 inches high, with an interior around 86.6 inches wide by 70.7 inches deep by 85.5 inches high. The manual also lists an assembled weight of approximately 1,875 lb. That number is important: the CL7G should be treated as a substantial backyard structure when planning a deck, platform or other supporting surface.

The CL7G also moves into a different heater category. Options include floor-standing and high-stone-mass options from Saunum, Harvia, HUUM and IKI rather than the smaller wall heaters used on the CL3G.

Choose the CL7G if You expect regular group use, want seating on both sides and have room for a much larger sauna footprint.

Stay with the CL5G if Four-person capacity is enough and you want a simpler site, freight and heater project.

View CL7G Current Price & Options

What size sauna heater does each SaunaLife Cube need?

This is the section where generic sauna advice often becomes unreliable. A common rule is to start with room volume and match it to the heater manufacturer's published range. Keep in mind that if there are other materials such as glass front you will need to obtain the adjusted volume. That is only the beginning for a glass-front outdoor sauna. Large glass surfaces change the effective heating load, and heater brands use their own sizing corrections, safety distances and control requirements.

For the Cube Series, the strongest starting point is the model-specific heater configuration. It gives us a real-world pairing list for the exact sauna model instead of asking you to guess from raw cubic footage.

If you want to browse the heater category separately, see our Sauna Heaters collection.

Harvia vs HUUM vs IKI vs Saunum: what changes besides kW?

Two heaters can have similar output and still create a very different installation plan. The biggest differences are mounting style, stone capacity, control system, safety clearances and how much floor or wall space the heater occupies. Its important to review the installation manuals in detail to understand safety clearances. The last thing you would want is the void the warranty by not staying in line with what has been specified.

Compact wall heaters: Harvia KIP and The Wall

The Harvia KIP and The Wall families keep the heater off the floor and use a relatively compact stone cavity. The KIP45B/KIP80B versions use built-in controls, while the KIP45W/KIP80W versions are intended for a separate control system. The Wall SW80/SWS80 is another compact 8 kW wall-mounted option for the CL4G and CL5G.

Higher-stone-mass designs: Spirit, HUUM, IKI and Cilindro

The Harvia Spirit, HUUM DROP/HIVE, IKI Pillar and Harvia Cilindro put more visible stone around the heat source. That can be appealing if you care about water-on-stone use and want a heater to become part of the sauna's visual design. It also means you need to take stone quantity, guard design and clearances seriously instead of choosing by appearance alone.

As a useful reference, Harvia lists about 44 lb of stones for the KIP and The Wall models, about 110 lb for the Spirit SP80E, while IKI lists about 286 lb for its 9 kW Pillar. HUUM's DROP is published at roughly 121 lb of stones, and the HIVE Mini family is designed around a much larger stone mass. More stone is not automatically “better”; it changes the character and installation of the heater.

Saunum Air L 10: a different approach for the CL7G

Saunum's Air L system combines the heater with an indoor climate device that circulates and blends hotter upper air with cooler lower air. It is a different design approach from a conventional wall or pillar heater, and the North American Air L must be paired with the specified Saunum control system. It is one of the reasons the CL7G heater list should be evaluated as a group of different systems, not just a list of wattages.

Built-in control vs separate control matters

If remote start or app control is important, decide that before ordering the heater. A built-in manual-control heater is deliberately simple. Separate-control models can support more advanced controllers, but the controller, sensors, door switch and power components become part of the installation. Do not assume that every heater shown for a Cube model includes Wi-Fi or can be remotely started in the same way.

Electrical planning: choose the heater before the rough-in

The sauna cabin and the sauna heater are separate parts of the project. SaunaLife's manuals direct owners to use qualified professionals for heater and lighting electrical work. The exact circuit, conductor size, controller and sensor layout depend on the heater you select and the electrical code that applies at your site.

For a deeper planning checklist, read our Sauna Electrical Requirements Guide.

What should a SaunaLife Cube sit on?

SaunaLife's installation manuals are consistent on the fundamentals: the sauna needs a stable, level, load-bearing foundation, and the site should avoid constant water exposure to the wood. That gives you several possible foundation approaches, but it does not create one universal slab or deck specification.

A concrete pad, properly designed deck or well-prepared paver/base system may all be possible depending on the model and site. The supporting structure needs to be appropriate for the actual sauna load, local soil and frost conditions, drainage, and any structural code requirements. The CL7G deserves particular attention because its technical drawing lists an assembled weight around 1,875 lb before you add bathers, heater and stones.

Plan drainage before the sauna arrives

Outdoor wood performs best when water can move away from the structure. Do not create a low spot where rain or runoff can remain against the foundation beams. The roof system helps manage weather above; the site has to manage water below.

Leave room for the door swing

The Cube manuals state that the sauna door must open outward. They also allow the door to be rotated 180 degrees during installation when you want the handle on the opposite side. That small detail can solve a real site-planning problem near stairs, fences, landscaping or a narrow patio.

Think about freight access, not just final footprint

These are large outdoor sauna kits with substantial published shipment weights. Before ordering, think through curbside access, where the shipment can be staged, how the glass components will be handled and how parts will move from the delivery point to the build location. A perfect 80-inch-wide patio does not help if the crated sauna cannot be moved through the path leading to it.

Why SaunaLife uses Thermo-Spruce outside and Thermo-Aspen inside

Across the Cube Series, SaunaLife uses thermally treated spruce for the main wood structure and Thermo-Aspen for the benches and backrests. SaunaLife's current specifications list 42 mm Thermo-Spruce wall construction, 28 mm front/back wall components and an 8 mm tempered bronze glass front.

That division of materials makes sense for how the sauna is used: the structural shell and outdoor surfaces have one job, while the surfaces your skin touches have another. The Thermo-Aspen seating also creates a lighter interior contrast against the darker exterior structure.

If you want a broader comparison of cedar, hemlock, aspen and spruce, read Best Wood for Sauna: Cedar vs Hemlock vs Aspen vs Spruce.

Does the full glass front affect heater sizing?

Yes. Glass does not insulate like a conventional insulated wall, so heater manufacturers account for uninsulated glass and similar surfaces when they calculate effective sauna volume. The exact correction method depends on the heater brand. This is another reason to use model-specific heater pairings and then confirm the selected heater's own sizing method.

What the glass front changes for the buyer

• View and openness: the full bronze glass front makes these cabins feel visually larger than an all-wood room.
• Privacy: think about which direction the sauna faces before the foundation is fixed.
• Cleaning: glass will show water spots and fingerprints more readily than wood.
• Heater planning: glass area is part of the heating-load calculation, not just an aesthetic feature.

How difficult is a SaunaLife Cube to assemble?

These are kits, not prebuilt rooms. The manuals call for common construction tools, careful glass handling, leveling, roof underlay and shingles, bench assembly, door installation, ventilation components and final exterior work. Electrical work is separate.

The smaller CL3G manual lists extra hands but does not call out a ratchet strap in its main tool list. The CL4G and CL5G manuals do. The CL7G goes further and specifies a ratchet strap at least 27 feet long. That is a useful signal of how the structural assembly becomes more involved as the cabin gets larger.

The full glass wall also deserves care during assembly. The manuals repeatedly warn installers not to strike the glass with screws or tools. If you are not comfortable handling large tempered-glass panels, hiring experienced help can be a sensible part of the project plan.

What ownership looks like after installation

SaunaLife's maintenance instructions are straightforward, but they should be part of the buying decision because this is an outdoor wood product.

• Protect the wood: SaunaLife recommends a suitable wood preservative at least once per year, or more often when conditions require it.
• Let the sauna dry: after cleaning, allow surfaces to dry fully with proper ventilation.
• Use a damp cloth on benches: do not wash the wood with running water or a pressure washer.
• Avoid paints, varnishes and harsh disinfectants: the manual warns these can damage the wood.
• Check hardware: heat and moisture cycles can loosen screws and affect door alignment over time.
• Inspect heater stones: stones can crack with use and should be replaced or added as required by the heater manufacturer.

SaunaLife's manuals also call for a supervised initial heat cycle of about two hours with good ventilation. The manual references around 210°F for that first cycle, but the selected heater's own maximum operating temperature and local requirements always take priority.

For stone selection and care, see Best Rocks for a Sauna: What to Use and Why.

Planning your SaunaLife Cube project with My Energy Flow

We can help with product and project planning, but final electrical design, structural verification, permitting and site-specific construction should be completed by the appropriate qualified professionals in your area.

Frequently asked questions about the SaunaLife Cube Series

Final recommendation: choose the layout first, then the heater

The easiest way to make a good decision is to work in this order: usable bench layout → site footprint → heater system → electrical plan → delivery and assembly. Starting with person capacity alone can push you toward a sauna that technically fits the right number of people but does not fit the way you want to use it.

For most one- or two-person households, the real decision is CL3G versus CL4G. For families or regular three- to four-person use, CL5G is the practical middle ground. CL7G makes sense when group seating is a genuine requirement rather than an occasional nice-to-have.

Manufacturer and technical references

Primary product and technical references: SaunaLife CL3G, SaunaLife CL4G, SaunaLife CL5G, SaunaLife CL7G, SaunaLife Technical Information, Harvia, HUUM, IKI Saunas USA, and Saunum North America.

Last reviewed: September 2026. Product specifications, heater availability and manufacturer recommendations can change. Confirm the current sauna drawing, heater installation manual, local electrical requirements and required safety clearances before ordering or installing equipment. My Energy Flow provides product-selection and planning support; licensed trades and local authorities should determine site-specific electrical, structural and permitting requirements.