Best Price and Service Guarantee

Sauna Marketplace offers legendary customer service and support. Odds are you landed here from a referral — because we don’t advertise.

That doesn’t mean you should have to pay more. We always honor the lowest prices allowed by our manufacturers. If you find a lower advertised price from an authorized dealer, send us a screenshot and we’ll match it.

We want you to feel great about your purchase for decades. That’s why we also offer free shipping on sauna accessories for life with the purchase of any sauna or sauna heater on Sauna Marketplace.

Shop Saunas | Shop Sauna Heaters

Specs
Made in
Model1×4 STS4 Cladding
Size10 Linear Feet, 6 Linear Feet, 7 Linear Feet, 8 Linear Feet, Free Sample
Nominal Thickness1″ (25.4mm)
Nominal Width4″ (101.6mm)
Actual Thickness0.59″ (15mm)
Wall Coverage3.1″ (80mm)
Weight (per linear foot)1 lb (0.5 kg)
Attachments
Gallery

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

A clean, classic sauna wall in the cladding width most builders start with. The 1×4 STS4 in thermo-aspen is a tongue-and-groove board, 0.59″ thick, milled 3.54″ wide for 3.1″ of coverage per row. The thermal modification takes it to a warm golden-brown that runs all the way through, so trimmed ends match the face and nothing reads as patchwork. Knot-free, no resin, stays cool against bare skin. Easy to run floor to ceiling and easy to pair with a contrasting bench or trim. Sold by the linear foot.

Build Your Quote:

Price range: $4.38 through $43.78

Shipping Unloading Notice

Ships Free With Any Sauna Heater Purchase

Shipping

Important: Only select ‘Flat Rate Shipping – $795’ once per order. For all other wood items you add, choose ‘Part of existing shipment’

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The default sauna wall. For good reason.

The PROSAUNAS Thermo-Aspen 1×4 T&G STS4 Wall Cladding is 0.59″ thick and 3.54″ wide, with 3.1″ of coverage once the tongue seats into the groove. Available in 6, 7, 8, and 10-foot lengths. This is the width most people picture when they picture a sauna: even, calm, and simple to run top to bottom without the wall getting busy.

Why Thermo-Aspen

Cladding is where thermal modification earns its keep. An untreated board in a hot, humid sauna will pull in moisture, swell against its neighbor, and over a few seasons the seams start to move. Thermo-aspen has already been through extreme heat and steam, no chemicals ever, which changes the wood at a cellular level so it can’t hold moisture and won’t expand and contract. The warm golden-brown color runs all the way through the board, so a cut end at the ceiling line matches the face and the room reads as one piece.

One honest note: every sauna wood is soft and will scratch, and thermal modification doesn’t change that. The upside is you can sand it back and refinish it years from now without hurting a thing.

Specifications

  • SKU: PS-THERMO-ASPEN-1X4-TG-STS4
  • Species: Thermo-Aspen (thermally modified)
  • Profile: 1×4 STS4 tongue-and-groove wall cladding
  • Actual width: 3.54" (3.1" coverage per row)
  • Actual thickness: 0.59"
  • Process: heat and steam only, no chemicals
  • Made in: Estonia
  • Sold by: the linear foot

Where it goes

Walls and ceilings. Pair it with our Thermo-Aspen or Thermo-Spruce bench wood for a matched interior, or run a wider profile as a contrast band. Narrower coverage means you use a few more linear feet per wall than a wide board, so do the math before you order and reach out if you want us to check it.

Shipping and samples

Sold by the linear foot. Shipping is a flat $795 in the continental US, or free with a heater order. Not sure on the board count? Text your name and address to (844) 565-1113 for free samples.

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

Best Price and Service Guarantee

Sauna Marketplace offers legendary customer service and support. Odds are you landed here from a referral — because we don’t advertise.

That doesn’t mean you should have to pay more. We always honor the lowest prices allowed by our manufacturers. If you find a lower advertised price from an authorized dealer, send us a screenshot and we’ll match it.

We want you to feel great about your purchase for decades. That’s why we also offer free shipping on sauna accessories for life with the purchase of any sauna or sauna heater on Sauna Marketplace.

Shop Saunas | Shop Sauna Heaters

Specs
Made in
Model1×4 STS4 Cladding
Size10 Linear Feet, 6 Linear Feet, 7 Linear Feet, 8 Linear Feet, Free Sample
Nominal Thickness1″ (25.4mm)
Nominal Width4″ (101.6mm)
Actual Thickness0.59″ (15mm)
Wall Coverage3.1″ (80mm)
Weight (per linear foot)1 lb (0.5 kg)
Attachments
Gallery

PLAN THE WHOLE SAUNA

The room and heater still have to work as one system.

Start with the room dimensions, then account for glass, masonry, insulation, ceiling height, required clearances, and available electrical service. That is how we move from a product that looks right to a sauna that heats evenly and comfortably.