Not all sauna timber is equal. We explain why Canadian hemlock has become the premium choice for sauna construction worldwide — and why every Gravity cabinet is built from nothing less.
## The Wood Beneath the Warmth
In a sauna, timber is not merely structural — it is the medium through which an experience is created. The wood you sit on, press your back against, and breathe beside affects how the sauna feels, performs, and ages. It is, accordingly, a choice that Gravity takes seriously.
## What Makes Canadian Hemlock Exceptional
Canadian hemlock (Tsuga canadensis) grows in the temperate rainforests of the Pacific Northwest and British Columbia. Its properties make it unusually well suited to sauna construction:
**Cellular density and heat absorption**: Hemlock's tight, straight grain creates a stable cellular structure that absorbs and radiates heat evenly. Unlike softwoods with loose grain, hemlock will not develop uncomfortable hot spots.
**Low resin content**: High-resin woods — pine, for instance — can produce sticky surfaces and acrid smells when heated repeatedly to sauna temperatures. Hemlock is naturally low in resin, creating a clean, neutral aromatic profile that most people find pleasant.
**Dimensional stability**: Wood in a sauna expands and contracts with each heating and cooling cycle. Hemlock's moderate density and tight grain minimise this movement, reducing the risk of warping, splitting, or joint failure over time.
**Natural resistance to moisture**: Hemlock has a natural resilience to moisture that suits it to the thermal cycling of regular sauna use, particularly in traditional saunas where steam is introduced.
**Splinter resistance**: A consideration often overlooked — hemlock's smooth, even surface is far less prone to surface splintering than lighter softwoods, making it genuinely pleasant to sit on with bare skin.
## Gravity's Sourcing Standards
Every piece of hemlock in a Gravity sauna is sourced from certified sustainable forestry operations. We select for consistent grain, appropriate moisture content, and freedom from knots or defects in contact surfaces.
Before despatch, each cabinet is inspected for quality of assembly and finish. This is not a cursory check — it is a hands-on review of every panel, joint, and connection.
## Alternatives and Why We Reject Them
Many sauna manufacturers use Nordic spruce, Scandinavian pine, or — at the lower end — poplar and basswood. These are functional materials, but none match the combination of properties that makes hemlock so well suited to the purpose.
Thermally modified woods (ThermoWood) offer excellent stability but can feel hard and lifeless compared to natural hemlock. Cedar, while fragrant and stable, is significantly more expensive and not universally liked for its strong aromatic profile.
Hemlock strikes the ideal balance: premium quality, pleasant in use, sustainable in sourcing, and enduring in performance.
Frequently Asked Questions
Does the hemlock wood require any treatment or oiling?
No chemical treatment is required or recommended. Wiping down the interior after use is sufficient. Over time, the wood will develop a natural patina from use — this is normal and desirable.
Will my sauna smell of wood?
New hemlock has a subtle, clean, slightly sweet wood scent that most users find pleasant. This fades over the first few weeks of use. Hemlock is notably free of the strong resinous smell associated with pine saunas.
How long will a Canadian hemlock sauna last?
With regular maintenance, a well-constructed hemlock sauna should last 20 years or more. The key factors are keeping the interior clean and dry between sessions, and inspecting the heater and electrical components annually.