PROSAUNAS Thermo-Spruce 1X4 T&G STS4 Wall Cladding – Sauna Wood

Under two dollars a board to start. The cheapest way into a real wood sauna.

This is natural Nordic Thermo-Spruce, 1×4 STS4: smoothed on all four sides with a tongue-and-groove edge that locks the boards into a tight, flush wall or ceiling. Light, rustic, with the tight knots that give a Finnish cabin its character, and a mild clean scent. We can mill it up to 14 feet, longer than most European stock runs.

Why spruce

Thermo-Spruce, aspen, and alder are what they actually line saunas with across Finland and Estonia, the places that invented the sauna. Cedar is a North American habit, not a global one. Thermo-Spruce is the floor of that European lineup: the most affordable way to get a genuine Nordic look.

The honest part, because we’d rather you hear it from us: this is natural spruce, not thermally modified. It will move a bit more than our Thermo-Spruce or Thermo-Aspen through the heat-and-cool seasons, and you may see slight gapping over the years. Want the same rustic look with thermal stability? Step up to Thermo-Spruce. It runs a deeper amber, holds tighter, and skips the seasonal movement. Want the lowest price into an authentic sauna? This is the board.

Specifications

• Species: Nordic Thermo-Spruce (natural, not thermally modified)
• Profile: 1×4 STS4 Tongue & Groove
• Face coverage: 3.1" per board
• Lengths: up to 14 ft
• Made in: Estonia
• Sold by: the linear foot

Where it goes

Walls and ceilings. For benches and backrests, most builders move up to aspen, which stays smoother and cooler under bare skin. We can help you mix the two.

Shipping and samples

Sold by the linear foot. Shipping is a flat $795 in the continental US, or free with a heater order. Text your name and address to (844) 565-1113 and we’ll send a sample free.

Call Ben² at (844) 565-1113 if you’d like to talk through the board count before you order.