The Carbon Smart™ 8’ × 9’ × 8’ Indoor Sauna Kit is a complete interior package for building a custom home sauna. It arrives with all interior components precisely cut to your room dimensions — tongue-and-groove wall and ceiling boards, benches, an all-glass door, flooring, ventilation grills, lighting, and accessories — all in Thermo Poplar, a thermally modified wood chosen for its dimensional stability and clean aesthetic. You supply the framing, insulation, electrical wiring, and exterior wall covering; we supply everything inside.
Why Customers Choose the Carbon Smart™ Kit
- All interior components are pre-cut to your room dimensions, reducing on-site labor
- Thermo Poplar is thermally modified without chemicals for enhanced stability and humidity resistance
- Includes an all-glass sauna door with wood handles, trim, and hardware
- Multiple accessory packages available: bench skirting, LED under-bench lighting, or both
- Optional Harvia WiFi electric heater bundles available — heater stones included with each heater option
- Suitable for both residential and light commercial sauna installations
- Detailed installation instructions included for DIY and contractor builds
Product Highlights
Thermo Poplar Wood
Thermo Poplar is a sustainably sourced wood thermally modified at approximately 374°F. The process — chemical-free — improves dimensional stability and resistance to humidity and temperature fluctuations, producing a warm, rich tone well-suited to sauna interiors.
All-Glass Sauna Door
The kit includes a full all-glass door with wood handles and trim. Frame dimensions are 27.2″ × 78.7″ (690 × 2000 mm); rough opening required is 28″ × 80″.
Pre-Cut Interior Components
Wall and ceiling boards, bench boards with supports, corner moldings, baseboards, and duckboard flooring are all cut to your specified room dimensions, arriving ready to install.
Customizable Bench Configuration
Choose from multiple bench layout options to suit your space and seating preferences. Each configuration uses 20″-deep clear Thermo Poplar bench boards with supports.
Optional Harvia WiFi Heater Bundles
Select from four Harvia WiFi electric heater options at checkout — Cilindro 11KW, Club 10KW, Virta 10.5KW, or Virta Combi 10.5KW — each bundled with heater stones included.
Marine-Grade Vapor-Proof Lighting
A wall-mount, marine-grade, vapor-proof sauna light is included with every kit, rated for the high-humidity sauna environment.
What’s Included
- Foil vapor barrier
- 1×4 tongue-and-groove wall and ceiling boards (Thermo Poplar)
- Clear 1×4 bench boards with supports, 20″ deep (Thermo Poplar, custom-built to chosen configuration)
- Ergonomic backrests
- Corner moldings for walls, ceiling, and baseboards (Thermo Poplar)
- All-glass sauna door with wood handles and trim (frame: 27.2″ × 78.7″; rough opening: 28″ × 80″)
- Duckboard flooring for walk area (Thermo Poplar)
- Upper and lower vent grills
- Traditional sauna bucket with liner and ladle
- Sauna thermometer
- Headrest
- Marine-grade, wall-mount, vapor-proof sauna light
- Detailed installation instructions
Specifications
| Room Dimensions | 8’ × 9’ × 8’ (W × L × H) |
| Wood Species | Thermo Poplar (thermally modified) |
| Board Profile | 1×4 tongue-and-groove |
| Bench Depth | 20 inches |
| Door Frame | 27.2″ W × 78.7″ H (690 × 2000 mm) |
| Door Glass | 24.4″ W × 77.3″ H (620 × 1963 mm) |
| Frame Thickness | 1.65″ × 3.6″ (42 × 92 mm) |
| Rough Opening Required | 28″ × 80″ |
| Recommended Ceiling Height | 8 feet |
| Shipping Weight | 800 lbs |
| Wood Type Option | Thermo Poplar |
| Accessory Options | No Accessories | Bench Skirting | LED Under-Bench Lighting | Luxury Package (Skirting + LED) |
| Heater Options | No Heater | Harvia Cilindro 11KW WiFi | Harvia Club 10KW WiFi | Harvia Virta 10.5KW WiFi | Harvia Virta Combi 10.5KW WiFi |
Heater Option Comparison
| Feature | Cilindro 11KW | Club 10KW | Virta 10.5KW | Virta Combi 10.5KW |
|---|---|---|---|---|
| Power Output | 11 KW | 10 KW | 10.5 KW | 10.5 KW |
| WiFi Control | Yes | Yes | Yes | Yes |
| App-Based Remote | Yes | Yes | Yes | Yes |
| Heater Stones Included | Yes | Yes | Yes | Yes |
| Safety Railing Included | No | No | Yes | Yes |
| Combi Steam Function | No | No | No | Yes |
| Design Style | Cylindrical, floor-standing | Floor-standing, commercial-grade | Wall-mounted, premium | Wall-mounted, premium + steam |
Key Differences at a Glance
- Cilindro 11KW: Highest output in the lineup at 11KW; iconic cylindrical design with large stone capacity
- Club 10KW: Floor-standing commercial-grade build at 10KW; suited to high-use environments
- Virta 10.5KW: Wall-mounted with safety railing included; 10.5KW with WiFi app control
- Virta Combi 10.5KW: Everything the Virta offers, plus an integrated steam generator for combined dry and steam sauna use
- All four models include heater stones and full WiFi app-based control
Ideal For
- Homeowners building a custom indoor sauna in a dedicated room
- DIY builders and professional contractors looking for pre-cut, ready-to-install interior components
- Buyers who want a thermally modified wood interior without chemical treatments
- Residential and light commercial sauna installations
- Projects where a bundled heater option simplifies procurement
Important Information
- This kit supplies interior components only. Framing, insulation, electrical wiring, and exterior wall covering are not included and must be provided on-site.
- Recommended ceiling height is 8 feet per manufacturer safety and clearance guidelines. For custom ceiling heights, contact us before ordering.
- Wall boards run horizontally by default. For rooms wider than 8 feet, an interior seam will be added where boards meet to span the full width.
- The kit ships with an all-glass door. Some product images may show a glass wall for reference; the door is the standard included component.
- Backrests ship flat. If an angled backrest is preferred, additional spacers can be fabricated on-site to achieve the desired pitch.
- If a heater option is selected, electrical installation must be performed by a licensed electrician. Consult local building and electrical codes before installation.
- If stones are ordered with a heater, they will ship in multiple boxes.
- This product is intended for sauna use only. Follow all manufacturer installation and safety guidelines.
Frequently Asked Questions
What does the Carbon Smart™ kit include?
The kit includes all interior sauna components: tongue-and-groove wall and ceiling boards, bench boards with supports, corner moldings, baseboards, duckboard flooring, an all-glass door with hardware, upper and lower vent grills, a vapor barrier, a sauna bucket with liner and ladle, a thermometer, a headrest, a marine-grade vapor-proof light, and installation instructions. Framing, insulation, electrical, and exterior wall covering are not included.
What is Thermo Poplar and why is it used?
Thermo Poplar is a sustainably sourced wood that has been thermally modified at approximately 374°F through a chemical-free process. This treatment improves dimensional stability and resistance to humidity and temperature changes — properties that make it well-suited to the demanding environment of a sauna interior.
Do I need to supply the heater separately?
A heater is optional. You can select one of four Harvia WiFi electric heater bundles at checkout (each includes heater stones), or choose “No Heater” if you plan to source a heater separately or already have one.
What rough opening does the sauna door require?
The all-glass door requires a rough opening of 28″ × 80″. The door frame dimensions are 27.2″ × 78.7″ (690 × 2000 mm).
Can I customize the ceiling height?
The standard kit is designed for an 8-foot ceiling height per manufacturer safety and clearance guidelines. If you need a custom ceiling height, contact us before placing your order.
What is the difference between the Virta and Virta Combi heater options?
Both are 10.5KW wall-mounted Harvia heaters with WiFi control, app-based remote, heater stones, and a safety railing included. The Virta Combi adds an integrated steam generator, allowing the unit to function as both a traditional dry sauna heater and a steam bath in one.
Is this kit suitable for commercial use?
The Carbon Smart™ kit is suitable for residential and light commercial sauna installations. For high-traffic commercial applications, contact us to discuss the right configuration and heater option for your project.
The Carbon Smart™ 8’ × 9’ × 8’ Indoor Sauna Kit gives you a complete, pre-cut Thermo Poplar interior with the flexibility to choose your bench configuration, accessory package, and heater. If you’re planning a home sauna build and want quality materials with straightforward installation, this kit is worth a close look. Order today or contact us with any questions — we’re here to help you get the right configuration for your space.
This product is intended for sauna use only. It is not a medical device and is not intended to diagnose, treat, cure, or prevent any condition or disease. Consult a qualified healthcare provider before use if you have any health concerns. Always follow the manufacturer’s installation and safety guidelines.