Western Red Cedar Tongue & Groove for Saunas — Clear MG, Kiln-Dried

Why Western Red Cedar Is the Gold Standard for Sauna Interiors

Western Red Cedar (Thuja plicata) is the traditional choice for sauna interiors in North America — and after building hundreds of saunas by hand in our Vancouver, Washington shop, it's the only wood we trust for the flagship Signature Sauna line. Four properties make cedar uniquely suited to sauna interiors:

• Natural rot and mildew resistance. Cedar's natural oils (thujaplicins) resist decay in high-humidity environments without any chemical treatment. That matters inside a sauna where wood absorbs and releases moisture with every session.
• Low thermal conductivity. Cedar's low density means it stays comfortable to touch at high heat. Sitting on a cedar bench at 190°F feels warm; sitting on a hardwood bench at the same temperature can burn skin.
• Dimensional stability. WRC has one of the lowest shrinkage-and-expansion ratings of any softwood, so boards stay tight and don't cup or twist through the repeated heat and moisture cycles a working sauna demands.
• Non-toxic and safe at high heat. Cedar releases its warm aroma but no harmful VOCs, resins, or pitch pockets that could off-gas in an enclosed hot room.

This listing is true clear grade Western Red Cedar — small tight knots at most, no loose knots, no pitch pockets, no defects. It's the same material milled to the same tolerances we use in our own build shop for our Signature Saunas. Kiln-dried to sauna-ready moisture content so boards don't cup, twist, or gap as they acclimate. Mixed-grain (MG) faces give you the full warmth of cedar's natural color variation without the price jump of vertical-grain-only stock.

👉 Want the full cedar species deep-dive? Read Japanese Cedar vs. Western Red Cedar: Choosing the Right Wood for Your Sauna for a side-by-side on aroma, density, oil content, and cost.

Horizontal vs. Vertical Cedar Installation — Which Direction Is Right for Your Sauna?

Both orientations are traditional in sauna construction. The choice comes down to the look you want, your build site's practical constraints, and — critically — how your framing is built. Before you pick an orientation, look at how your wall studs run:

• Horizontal cedar (parallel to floor) — easier install: The most common orientation for compact indoor saunas because standard wall framing has vertical studs at 16" or 24" on center, giving you a solid nailer every foot or two as you work up the wall. You nail the T&G tongue directly into each stud you cross. No extra framing prep required. Also makes the room feel wider, allows longer continuous board runs on the long walls, and works well when your ceiling height doesn't cleanly divide by 3" (fewer awkward rip cuts at the ceiling line). Traditional Finnish and North American home saunas typically use horizontal cedar for exactly this reason.
• Vertical cedar (parallel to studs) — requires additional blocking: Because your studs already run vertical, the T&G would be running parallel to them instead of crossing them — meaning you have nothing to nail into between the top and bottom plates. Before installing vertical cedar you'll need to add horizontal blocking (2×4 nailers) between the studs, typically every 24" of wall height, so the T&G has something to bite into. Plan an extra half-day of framing prep per wall. The trade-off: vertical cedar sheds condensation better (water runs straight down between the boards rather than pooling on horizontal joints), makes the room feel taller, and is often preferred for outdoor saunas, barrel saunas, and high-use commercial installs where every session generates heavy löyly.
• Ceilings — same rule: If your ceiling joists run one direction, board runs that cross them install straight to the joists. Runs that go parallel to the joists need blocking added between them.
• Mix and match: Some of our Signature Sauna builds use vertical cedar on the walls (with blocking added during framing) and horizontal on the ceiling for a "boat interior" look. The calculator above lets you set each surface independently so you can price both approaches before committing.

What You're Getting

• True clear-grade Western Red Cedar — the top grade offered by Pacific Northwest mills. No industrial knots, no defects. See the WRCLA grade standards for reference.
• Nominal 1" × 4" tongue & groove profile with a 3" face reveal — the industry-standard sauna interior profile.
• Kiln-dried to the moisture content that keeps boards stable through your first heat cycles — no post-install cupping or gapping.
• Non-toxic, chemical-free surface — no stains, no sealants, no finishes required. Safe for high-heat, closed-air sauna interiors.
• Sold by the linear foot so you order exactly what your project needs, not by the pallet.
• Mill lengths 4', 6', 8', 10', 12' to match your cut list. Longer custom lengths available on request.

How NW Immersion WRC T&G Compares

Building a Complete Sauna? Here's What Else You'll Need

Cedar T&G is one piece of the puzzle. A complete sauna build typically also needs:

• Foil vapor barrier behind the cedar to keep moisture out of the framing
• Sauna heater and stones — Harvia, HUUM, and Saunum options in stock
• Sauna door — tempered glass or solid cedar
• Cedar benches and backrests — clear cedar or knotty aspen
• Heat-rated sauna lighting — recessed or wall-mount
• Sauna-rated red light panel — for combined red-light and heat therapy
• Sauna bucket and ladle — for löyly and steam

Not sure exactly what quantities you need? Read our guides on how to build an indoor sauna and how to build an outdoor sauna, or email info@nwimmersion.com with your sauna's interior dimensions and we'll build a complete materials list. Contractors, custom sauna builders, and DIY builders welcome.

Real Customer Cedar Builds

Verified 5-star reviews from customers who purchased WRC tongue and groove from NW Immersion and used it to build their own saunas. Reviews and photos pulled directly from our Google Business Profile.

★★★★★ Andy Muonio · Verified Google Review

"Purchased T&G cedar from NW Immersion. High quality product and the tips for install was a plus!"

★★★★★ Brandon Mendenhall · Verified Google Review

"NW Immersion has been a great help during my sauna build. I found them a little late in the build process, but right in time. I was able to get beautiful tongue and groove clear cedar. I gave Eric my dimensions and he got me setup with exactly what I needed. Then to finish things out, he setup me up with cedar for my benches and walked me through the tips and tricks of making the style bench that he puts in his custom builds. […] I would recommend NW Immersion if you are looking for someone else to build a custom setup for you, and if you don't use them for a build you are working on yourself you are missing out on great pricing, and a wealth of knowledge and experience."

Have questions about your own build? Email info@nwimmersion.com or read all 22 five-star Google reviews.

Western Red Cedar T&G — Frequently Asked Questions