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Choosing sauna timber, made simple.

Walls and benches do different jobs, so they often use different timber. Here's what each one is like, what it suits, and what we keep in stock in Auckland.

The short version

Two jobs, two kinds of timber.

Walls and ceilings set the look and the smell of the room. Benches are the part your skin actually touches, so they need to stay cool, smooth and resin-free.

Whatever you choose, use proper kiln-dried, sauna-grade timber. Construction timber has looser knots and more resin, and in 90 °C heat that means sticky, hot sap and boards that move. We import ours from Finland and Estonia.

Timber	Look	Best for
Spruce	Pale, knotty, forest scent	Walls, budget benches
Aspen	Creamy white, knot-free	Walls and benches
Abachi	Pale straw, fine grain	Benches
Thermo alder	Warm golden-brown	Walls and benches
Thermo aspen	Soft honey tone	Walls

Panelling

For walls and ceilings.

The traditional one

Spruce

If you've ever sat in a Finnish sauna, you were probably surrounded by spruce. Light, almost white when new, with small tight knots and a mild forest scent when it warms up. It handles heat and humidity well and slowly mellows to a golden honey colour.

Authentic Nordic look and smell
Light colour brightens small rooms
Great value

Worth knowing: Knots are part of the look. Sweat and oils can stain it, so use towels.

In stock: 15 × 95 mm · from $20.86/m See sizes and prices

Clean and calm

Aspen

Pale, creamy and knot-free, aspen gives a bright, modern, spa-like room. It's resin-free and almost odourless, so there are no sap pockets and no strong smell, which suits people with sensitive skin or noses.

Knot-free, uniform look
Resin-free and nearly odourless
Makes a small sauna feel bigger

Worth knowing: Shows marks more than darker timber.

In stock: 15 × 70 mm, 15 × 90 mm · from $20.70/m See sizes and prices

Warm and rich

Thermo alder

Alder that's been heat-treated at high temperature, with no chemicals. That turns it a warm golden to reddish brown, makes it more stable, and lowers its moisture content, so it's less prone to swelling, warping and cracking in the heat.

Rich, warm colour right through the board
More stable than untreated timber
Mild, slightly sweet smell

Worth knowing: A premium price. Darker look, not the classic pale Nordic room.

In stock: 15 × 90 mm · from $29.27/m See sizes and prices

Honey-toned aspen

Thermo aspen

Aspen given the same heat treatment, for a soft honey tone with aspen's clean, knot-free surface.

Knot-free and stable
Soft honey colour

In stock: 15 × 90 mm · from $42.60/m See sizes and prices

Exclusive to FinnSauna

Respect STS3

A thin layer of thermo-alder over an engineered lamella core, built to stay flatter and straighter than solid boards. Narrow square grooves give a crisp, modern look.

Very stable
Modern square-groove profile
Smarter use of timber

In stock: 15 × 120 mm · from $60.72/m See sizes and prices

Benching

For benches and backrests.

The classic bench timber

Abachi

Also called ayous or obeche. Abachi stays cool to the touch even in a hot sauna, has a fine, splinter-free grain and no resin. Pale straw colour, soft and comfortable to sit on.

Stays cool to the touch
Splinter-free and resin-free
Comfortable, soft hardwood

Worth knowing: Pale and porous, so it stains without towels and oil. Harder to source and pricier than it used to be.

In stock: 25 × 95 mm · from $78.21/m See sizes and prices

Smooth and pale

Aspen

Aspen benches sand up beautifully smooth and stay that way. Low heat conductivity means no 'ouch' when you sit down, and being resin-free and nearly odourless makes it a favourite for sensitive skin.

Cool to the touch
Very smooth, splinter-free
Clean, knot-free look

In stock: 28 × 120 mm, 28 × 90 mm · from $62.57/m See sizes and prices

Traditional and affordable

Spruce

The budget-friendly traditional choice. Use clear, kiln-dried, sauna-grade spruce for benches, so you're not sitting on loose knots or weeping resin.

Traditional look and scent
Most affordable option

Worth knowing: Choose sauna-grade boards with tight knots.

In stock: 28 × 95 mm · from $24.40/m See sizes and prices

Warm, stable and solid

Thermo alder

Heat-treated alder in the same warm tone as thermo-alder walls. Stable, resin-free and comfortable at full heat. Our wide 28 × 120 mm board makes a generous bench.

Matches thermo-alder and Respect walls
Stable in heat and humidity

Worth knowing: Premium price.

In stock: 25 × 90 mm, 28 × 120 mm, 28 × 90 mm · from $32.63/m See sizes and prices

Profiles explained

STP, STS3, SHP: what the letters mean.

The profile is the shape of the board's edge. It decides how the joins between boards look on the wall or bench.

STP

Wall panel with narrow grooves and rounded edges, giving the walls a smooth, soft look. One of the most common sauna wall profiles, and it combines well with others.

STS3

Wall panel with narrow square grooves for a crisp, modern shadow line. Used for our Respect panelling.

SHP

Bench board with softly rounded corners. Simple, classic, and comfortable against bare skin.

Look after it

Towels, oil, and decades of use.

Pale timber shows sweat and skin oils over time. Sit on a towel, and treat benches with a penetrating product that soaks in, never lacquer or varnish.

We stock clear Supi Sauna Wax and Sauna Paraffin Oil for exactly this.

Sauna care All timber

Not sure?

Tell us about the room.

Send a few measurements and photos, and how you want it to feel: bright and Nordic, warm and dark, or somewhere in between. We'll suggest a combination and work out the quantities.

Ask us

Choosing sauna timber, made simple.

Two jobs, two kinds of timber.

For walls and ceilings.

Spruce

Aspen

Thermo alder

Thermo aspen

Respect STS3

For benches and backrests.

Abachi

Aspen

Spruce

Thermo alder

STP, STS3, SHP: what the letters mean.

STP

STS3

SHP

Towels, oil, and decades of use.

Tell us about the room.

Let's talk about your next sauna.