Leisurecraft Launches CT Element Indoor Sauna with Thermo Grandis Wood

Leisurecraft, the Ontario-based manufacturer known for its barrel and cabin saunas, is launching the CT Element: a glass-fronted indoor sauna line in three sizes, designed for home wellness rooms, commercial gyms, and spa facilities. The line sits under Leisurecraft’s Canadian Timber Collection and represents a clear push upmarket from the company’s outdoor roots.

The defining feature is not the glass or the geometry. It is the wood. CT Element is built from Thermo Grandis, a thermally modified eucalyptus that breaks with the cedar-and-aspen consensus that has defined North American indoor saunas for decades. That choice makes the CT Element worth examining on its own terms, and worth measuring against the European-made competitors it now shares a category with.

Three Sizes, One Material Standard

The CT Element comes in Nook (roughly 4.5 x 4.5 feet, a two-person compact), Loft (4.5 x 6.2 feet, the mid-size option), and Studio (5.3 x 7 feet, the largest and most commercially viable of the three). All share the same material stack: Thermo Grandis throughout, 3/8-inch tempered glass on the front wall, triple-layer wall construction, a complete framed floor, and wide two-tier benching at 20 inches (upper) and 15 inches (lower).

Assembly uses pre-framed panels designed for dealer and contractor installation. Electric heater compatibility is standard, though Leisurecraft sells the heater separately, giving buyers flexibility to spec their preferred brand and output.

The fit and finish positions CT Element above Leisurecraft’s barrel and cabin lines. The company describes it as “closer to furniture than equipment,” and the clean geometry and full glass front support that framing. For operators and designers specifying indoor saunas for commercial wellness spaces, the question is whether the substance matches the look.

The Wood: What Thermo Grandis Actually Is

This is where CT Element gets interesting, and where buyers should pay attention.

“Thermo Grandis” is thermally modified Eucalyptus grandis, a plantation hardwood grown primarily in South America and southern Africa. The thermal modification process (heating to 375–450°F in a low-oxygen steam environment for 24 to 96 hours) fundamentally changes the wood’s properties. Equilibrium moisture content drops from roughly 12–15% to 4–6%. Volumetric swelling decreases by about 35%. Decay resistance improves by a wide margin.

Research at Brazil’s Universidade Federal do Espírito Santo found that fungal weight loss dropped from 34.3% for untreated eucalyptus to 6.05% after thermal modification at 430°F, an 82% improvement. The resulting wood is dimensionally stable, moisture-resistant, and carries a deep reddish-brown color that penetrates the entire board rather than sitting on the surface.

In those respects, Thermo Grandis is genuinely well suited to a sauna enclosure. It will not warp, cup, or decay the way untreated softwoods can, and its color will age gracefully rather than graying.

But eucalyptus is a dense hardwood, and that creates a specific trade-off. Dense woods conduct heat faster than lighter ones. When you sit on a Thermo Grandis bench at 185°F, the wood will feel noticeably warmer against bare skin than a bench made from lighter species. The thermal conductivity of a dense modified hardwood runs roughly 0.11–0.14 W/m·K, compared to about 0.09–0.10 W/m·K for thermo-aspen (the wood Auroom builds around) and roughly 0.09 W/m·K for obeche (the bench wood in Kohler’s C1 line).

That is not a safety concern, and many sauna users will not notice the difference at moderate temperatures or shorter sessions. But at high heat and on longer sits, bench wood species matters more than most product spec sheets acknowledge. The competitors charging more for this category have made deliberate, science-driven choices about bench surfaces, and those choices are worth understanding.

Where CT Element Sits: Auroom and Kohler Charge More for Good Reasons

The North American indoor sauna market has stratified over the past two years, and CT Element lands squarely in the middle.

At the top of the segment sits Kohler, which acquired KLAFS (the world’s largest sauna manufacturer by volume) in January 2024 and now sells the C1 indoor sauna in the United States starting at $17,900 USD. The C1 uses Scandinavian spruce for its enclosure and obeche for its benches. Obeche is one of the lightest, lowest-conductivity hardwoods commercially available, chosen specifically because it stays comfortable against bare skin at the highest sauna temperatures. Kohler adds 2.1 inches of mineral wool insulation, publishes precise dimensional specs for every size, and backs the product with its established service network. For $18,000 to $25,000, a buyer gets KLAFS engineering lineage, purpose-selected bench wood, and the institutional confidence of a brand with over a century of history.

Auroom, the Estonian manufacturer backed by Thermory (one of the world’s leading producers of thermally modified wood), takes a different approach. Auroom builds exclusively with thermo-aspen and thermo-alder: lightweight species with low thermal conductivity that Thermory has spent decades perfecting through its own modification process. Thermo-aspen is arguably the most purpose-built bench wood in the sauna industry: dimensionally stable, rot-resistant, and light to the touch even at peak temperatures. Auroom’s indoor lines start around $4,500–$7,000 USD at authorized dealers (before heater), with designer collaborations (including Italian architect Luca Donazzolo) and options like full glass walls and bronze-tinted glass pushing into higher territory. The premium buys wood science from people who have built an entire business around optimizing thermal modification, plus a level of design intent that few manufacturers in this space attempt.

CT Element slots below both. With the Nook starting around $10,800 CAD (approximately $7,900 USD), it offers a modern, glass-fronted indoor sauna from a North American manufacturer at a price point that undercuts Kohler by nearly half. The trade-off is in the wood: Thermo Grandis is durable, stable, and handsome, but it is not the purpose-optimized bench wood that the higher-priced competitors have invested in selecting.

What the Wood Choice Signals

Leisurecraft’s decision to build CT Element around Thermo Grandis rather than the Western Red Cedar that has defined their barrel and cabin lines is a deliberate material shift. Cedar, for all its aromatic appeal and sauna heritage, loses its natural rot resistance as the protective oils evaporate over years of heat cycling. Thermally modified wood’s durability is structural (baked into the cellular chemistry of the wood itself) and permanent. On that basis alone, the move to thermal modification makes sense.

The question is species selection. Auroom and Thermory built their sauna businesses around modified aspen and alder because those species start light and stay light after treatment. Eucalyptus grandis starts dense. While thermal modification reduces its density by roughly 12%, it remains a heavier, more thermally conductive wood than the softwoods and lightweight hardwoods that anchor the premium tier.

For a gym, a hotel wellness suite, or a multifamily amenity room where sessions tend to be shorter and temperatures moderate, the density difference is likely a non-issue. For a dedicated home sauna user running long sessions above 190°F, or for a Finnish-style sauna purist who prioritizes bench comfort at high heat, the premium woods in Auroom’s and Kohler’s lines justify the price gap.

There is also a supply chain story worth watching. CT Element is manufactured in Canada, which under current trade conditions avoids the tariff exposure that affects European imports into the United States. For commercial buyers specifying indoor saunas at scale, that origin advantage is real and may widen if trade policy continues to favor North American sourcing.