The Carbon Smart™ 6' × 8' × 8' Indoor Sauna Kit gives you everything needed to finish a professional-quality sauna interior—precisely cut Thermo Poplar components, an all-glass door, benches, lighting, and accessories—so you can focus on framing and finishing rather than sourcing materials. Whether you're a homeowner tackling a weekend build or a contractor outfitting a commercial space, this kit delivers consistent, high-quality results at a competitive price point.
Why Customers Choose This Kit
- All interior components are pre-cut to your room dimensions—no guesswork, no waste
- Thermo Poplar wood is thermally modified without chemicals for lasting dimensional stability
- Multiple Harvia heater upgrades available, including WiFi-enabled models for app-based control
- Optional accessory packages (bench skirting, LED under-bench lighting, or both) let you customize the finish
- Includes a complete accessory set: bucket, ladle, thermometer, headrest, and vapor-proof light
- Detailed installation instructions support both DIY and professional builds
- Responsibly sourced wood supports carbon-smart forestry practices
Product Highlights
Thermo Poplar Interior
All wall boards, ceiling boards, bench boards, and trim are crafted from Thermo Poplar—a sustainably sourced wood thermally modified at approximately 374°F. The process enhances dimensional stability and resistance to humidity without the use of chemicals, resulting in a warm, rich tone that holds up well in high-heat environments.
All-Glass Sauna Door
The kit includes a full all-glass door with wood handles and trim. The door frame measures 27.2" × 78.7" (690 × 2000 mm) and requires a rough opening of 28" × 80", fitting standard interior framing without modification.
Customizable Bench Layout
Choose from multiple bench configurations shown in the product images. Each layout is designed to maximize usable seating area within the 6' × 8' footprint. Bench boards are 20" deep and built to your selected configuration.
Harvia Heater Options
Select from six Harvia 8KW heater models at checkout—ranging from a straightforward built-in control panel to fully WiFi-enabled units with app-based scheduling. All heater options include sauna stones. The Harvia Virta also includes a protective safety railing.
Accessory Packages
Upgrade your finish with optional bench skirting, LED under-bench lighting, or the Luxury Package combining both. These add-ons are selected at checkout and shipped with your kit.
Vapor-Proof Lighting & Ventilation
A marine-grade, wall-mount, vapor-proof sauna light is included. Upper and lower vent grills are also provided to support proper air circulation throughout the sauna room.
What's Included
- Foil vapor barrier
- Ergonomic backrests
- 1×4 tongue & groove wall and ceiling boards – Thermo Poplar
- Clear 1×4 bench boards with supports (20" deep) – Thermo Poplar, built to your chosen configuration
- 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
| Interior Dimensions | 6' × 8' × 8' (W × D × H) |
| Recommended Ceiling Height | 8 feet |
| Wood Species | Thermo Poplar (thermally modified, chemical-free) |
| Modification Temperature | Approximately 374°F |
| Board Profile | 1×4 tongue & groove |
| Bench Depth | 20 inches |
| Door Frame Size | 27.2" × 78.7" (690 × 2000 mm) |
| Door Glass Size | 24.4" × 77.3" (620 × 1963 mm) |
| Door Frame Thickness | 1.65" × 3.6" (42 × 92 mm) |
| Rough Opening Required | 28" × 80" |
| Heater Power (optional) | 8 KW (all Harvia models) |
| Wall Board Direction | Horizontal (standard); interior seam added if room width exceeds 8 ft |
| Shipping Weight | Approximately 800 lbs |
| Product Type | Indoor Sauna Kit (interior components only) |
Sauna Heater Comparison
| Feature | Harvia KIP80B 8KW | Harvia Cilindro PC80 8KW | Harvia KIP80W 8KW | Harvia Cilindro PC80E 8KW | Harvia Spirit 8KW | Harvia Virta 8KW |
|---|---|---|---|---|---|---|
| Power Output | 8 KW | 8 KW | 8 KW | 8 KW | 8 KW | 8 KW |
| Control Type | Built-in | Built-in | WiFi | WiFi | WiFi | WiFi |
| WiFi Connectivity | No | No | Yes | Yes | Yes | Yes |
| Heater Stones Included | Yes | Yes | Yes | Yes | Yes | Yes |
| Railing Included | No | No | No | No | No | Yes |
| Remote Control | Manual only | Manual only | App-based | App-based | App-based | App-based |
| Model Series | KIP | Cilindro | KIP | Cilindro | Spirit | Virta |
Harvia KIP80B 8KW – Built-in Control
Harvia Cilindro PC80 8KW – Built-in Control
Harvia KIP80W 8KW – WiFi
Harvia Cilindro PC80E 8KW – WiFi
Harvia Spirit 8KW – WiFi
Harvia Virta 8KW – WiFi + Railing
Ideal For
- Homeowners building a dedicated sauna room in a basement, garage, or spare room
- Contractors and builders outfitting residential or commercial wellness spaces
- Spa and gym operators looking for a durable, professionally finished sauna interior
- DIY builders who want pre-cut, matched components without custom fabrication
- Anyone seeking a complete kit with heater, accessories, and interior finish in one order
Important Information
- This kit supplies interior components only. Framing, insulation, electrical wiring, and exterior wall covering are the responsibility of the installer.
- Recommended ceiling height is 8 feet per manufacturer safety and clearance guidelines. For custom ceiling heights, contact our support team before ordering.
- Electrical installation for the sauna heater must be performed by a licensed electrician in accordance with local building codes.
- Wall boards run horizontally by default. If room width exceeds 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 photos may show a glass wall panel for reference purposes only.
- Backrests are shipped flat. Angled positioning can be achieved on-site using spacers cut to the desired pitch.
- This product is intended for indoor residential or commercial use only. Do not install in outdoor or unenclosed environments.
- Always follow the heater manufacturer's installation and safety guidelines when selecting and installing a sauna heater.
Frequently Asked Questions
What does this kit include?
The kit includes all interior sauna components: Thermo Poplar tongue & groove wall and ceiling boards, bench boards and supports, corner moldings, duckboard flooring, an all-glass door with wood handles and trim, foil vapor barrier, ergonomic backrests, upper and lower vent grills, a sauna bucket with liner and ladle, thermometer, headrest, vapor-proof light, and installation instructions. Framing, insulation, electrical, and exterior finishing are not included.
Do I need a contractor to install this kit?
The interior components are designed for straightforward assembly and can be installed by a capable DIYer. However, electrical work for the sauna heater must be completed by a licensed electrician. Framing and insulation may also require a contractor depending on your local building codes.
Is a heater included?
A heater is not included by default. You can add one of six Harvia 8KW heater models at checkout—ranging from a built-in control panel to WiFi-enabled units with app-based scheduling. All heater options include sauna stones. The Harvia Virta also includes a protective safety railing.
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. This chemical-free process improves the wood's dimensional stability and resistance to humidity and temperature fluctuations—properties that are important in a high-heat sauna environment. It also produces a warm, rich tone suited to a premium interior finish.
Can I customize the bench configuration?
Yes. Multiple bench layouts are available and shown in the product images. Bench boards are 20" deep and built to your selected configuration. Select your preferred layout when placing your order.
What accessory packages are available?
Three accessory upgrades are available at checkout: Bench Skirting, LED Under Bench Lighting, and the Luxury Package which includes both. These are shipped with your kit and installed during the finishing stage of your build.
What rough opening is required for the door?
The all-glass door requires a rough opening of 28" × 80". The door frame measures 27.2" × 78.7" (690 × 2000 mm) and the glass panel measures 24.4" × 77.3" (620 × 1963 mm).
What if my room width exceeds 8 feet?
Wall boards run horizontally by default. If your room width exceeds 8 feet, an interior seam will be added where two boards meet to span the full width. This is a standard construction detail and does not affect the structural integrity or appearance of the finished sauna.
Can this kit be used in a commercial setting?
Yes. The Carbon Smart™ kit is suitable for both residential and commercial installations, including spas, gyms, and wellness facilities. Contact our team for guidance on commercial orders or multi-unit projects.
The Carbon Smart™ 6' × 8' × 8' Indoor Sauna Kit is a well-specified, complete interior package built around durable Thermo Poplar components and flexible configuration options. If you're ready to move forward or have questions about heater selection, bench layout, or accessory packages, our team is available to help you configure the right build for your space.
This product is a sauna construction kit intended for personal or commercial use. It is not a medical device and is not intended to diagnose, treat, cure, or prevent any health condition. Consult a qualified healthcare provider before use if you have any medical concerns.