Expert help that stays with you

Small details become expensive problems once installation begins. We ask the questions early, so a mismatched part, an overlooked requirement or an installation issue gets caught while it is still easy to fix.

Our job does not end when your order ships. We stay available through installation and beyond. If something needs attention, we stay involved, work the problem, and help see it through.

We want you to feel good about choosing Sauna Marketplace long after your first session, and confident recommending us to a friend. That standard guides the advice we give, the products we sell, and the way we take care of our customers.

Sauna and heater customers also receive free shipping on sauna accessories for life.

Planning a sauna, or need help with one you purchased from us? Our founders have built saunas from the crate up and both run saunas at home. New customers and existing Sauna Marketplace sauna and heater owners can Open the 3D planner.

Specs
Made in
Model1×5 STS4 Cladding
Size10 Linear Feet, 6 Linear Feet, 7 Linear Feet, 8 Linear Feet, Free Sample
Nominal Thickness1″
Nominal Width5″
Actual Thickness0.59″
Wall Coverage4.3″
Weight (per linear foot)1 lb
Attachments
Gallery

PROSAUNAS Thermo-Aspen 1X5 T&G STS4 Wall Cladding – Sauna Wood

A little more width, a little more calm. The 1×5 STS4 in thermo-aspen is a tongue-and-groove board, 0.59″ thick, milled 4.72″ wide for 4.3″ of coverage per row, so the wall reads with fewer seams across a given run. The thermal modification gives it a warm golden-brown tone all the way through, so cut ends match the face. Knot-free, no resin, stays cool to the touch. A clean choice when you want a broad, quiet wall. Sold by the linear foot.

Build Your Quote:

$6.76 per linear footFree samples available

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Free sample · Free shipping · No payment needed

One per wood. Ships within the continental US (lower 48 and DC).

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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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Wider boards. Fewer seams. A quieter wall.

The PROSAUNAS Thermo-Aspen 1×5 T&G STS4 Wall Cladding is 0.59″ thick and 4.72″ wide, with 4.3″ of coverage once the tongue seats into the groove. Available in 6, 7, 8, and 10-foot lengths. The extra width over a 1×4 means fewer board lines across a wall, which reads broader and calmer, and covers a given surface in less linear footage.

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-1X5-TG-STS4
  • Species: Thermo-Aspen (thermally modified)
  • Profile: 1×5 STS4 tongue-and-groove wall cladding
  • Actual width: 4.72" (4.3" 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, especially larger rooms where the wider board keeps the wall from looking busy. Pair it with our Thermo-Aspen or Thermo-Spruce bench wood for a matched interior. Do the math on coverage before you order and reach out if you want us to check the board count.

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.

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Planning guides: Choosing sauna woodSauna vapor barrier guide

Expert help that stays with you

Small details become expensive problems once installation begins. We ask the questions early, so a mismatched part, an overlooked requirement or an installation issue gets caught while it is still easy to fix.

Our job does not end when your order ships. We stay available through installation and beyond. If something needs attention, we stay involved, work the problem, and help see it through.

We want you to feel good about choosing Sauna Marketplace long after your first session, and confident recommending us to a friend. That standard guides the advice we give, the products we sell, and the way we take care of our customers.

Sauna and heater customers also receive free shipping on sauna accessories for life.

Planning a sauna, or need help with one you purchased from us? Our founders have built saunas from the crate up and both run saunas at home. New customers and existing Sauna Marketplace sauna and heater owners can Open the 3D planner.

Specs
Made in
Model1×5 STS4 Cladding
Size10 Linear Feet, 6 Linear Feet, 7 Linear Feet, 8 Linear Feet, Free Sample
Nominal Thickness1″
Nominal Width5″
Actual Thickness0.59″
Wall Coverage4.3″
Weight (per linear foot)1 lb
Attachments
Gallery