The Carbon Smart™ Indoor Sauna Kit gives you everything you need to build a professionally finished, full-size sauna room in a generous 7′ × 10′ × 8′ footprint—ideal for larger spaces, multi-person use, or premium home installations. Precision-cut Thermo Poplar components, a full-glass door, benches, lighting, and accessories arrive ready to install. You supply the framing, insulation, electrical, and exterior wall covering; we handle the rest.
Why Customers Choose This Kit
- Spacious 7′ × 10′ footprint accommodates multi-person use and larger bench configurations
- Complete interior package—no sourcing individual components separately
- Thermo Poplar wood is thermally modified without chemicals for lasting stability
- Configurable bench layouts to fit your space and preference
- Optional high-output 10–11KW Harvia WiFi heater bundles—add at checkout
- Optional accessory upgrades: bench skirting, LED under-bench lighting, or both
- Detailed installation instructions included for DIY or contractor builds
- Suitable for residential and light commercial installations
Product Highlights
Thermo Poplar Interior Wood
Sustainably sourced and thermally modified at approximately 374°F, Thermo Poplar delivers enhanced dimensional stability and improved resistance to humidity—achieved through a chemical-free process. The result is a warm, rich tone that holds up in high-heat sauna environments.
Full-Glass Sauna Door
The included all-glass door with wood handles and trim fits a 28″ × 80″ rough opening (frame: 27.2″ × 78.7″; glass: 24.4″ × 77.3″). It provides a clean, modern look while maintaining proper heat retention.
Configurable Bench Layouts
Choose from multiple bench configurations shown in the product images. Each layout uses 20″-deep clear Thermo Poplar bench boards with supports, custom-built to your selected configuration.
Proper Ventilation & Moisture Control
Upper and lower vent grills promote healthy air circulation, while the included foil vapor barrier protects your wall assembly from moisture damage over time.
Marine-Grade Vapor-Proof Lighting
A wall-mount, marine-grade vapor-proof sauna light is included—rated for the high-humidity sauna environment and ready to wire into your electrical plan.
Optional High-Output Harvia Heater Bundles
Select a 10–11KW Harvia WiFi heater at checkout—all models are app-controlled and include heater stones. The Virta Combi adds an integrated steam function for a combined sauna and steam experience. See the comparison chart below for details.
What's Included
- Foil vapor barrier
- Ergonomic backrests (shipped flat; on-site spacers can create an angled pitch)
- 1×4 tongue & groove wall and ceiling boards – Thermo Poplar
- Clear 1×4 bench boards with supports (20″ deep) – Thermo Poplar, custom to your configuration
- Corner moldings for walls, ceiling, and baseboards – Thermo Poplar
- All-glass sauna door with wood handles and trim (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 | 7′ × 10′ × 8′ (interior) |
| Recommended Ceiling Height | 8 feet (per manufacturer safety guidelines) |
| Wood Species | Thermo Poplar (thermally modified, chemical-free) |
| Wall & Ceiling Boards | 1×4 tongue & groove, horizontal run (interior seam added on 10-ft wall spans) |
| 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 Options (optional) | Harvia Cilindro 11KW WiFi, Harvia Club 10KW WiFi, Harvia Virta 10.5KW WiFi, Harvia Virta Combi 10.5KW WiFi |
| Accessory Options | No Accessories / Bench Skirting / LED Under-Bench Lighting / Luxury Package (both) |
| Shipping Weight (approx.) | 800 lbs |
| Brand | Finnish Sauna Builders – Carbon Smart™ Line |
Ideal For
- Homeowners with larger dedicated rooms, basements, or garage conversions
- Multi-person sauna use requiring generous bench space and headroom
- DIY builders and contractors looking for precision-cut, ready-to-install components
- Premium residential wellness rooms, home gyms, and spa additions
- Light commercial installations such as boutique fitness studios or wellness centers
- Buyers who want a complete kit with optional high-output heater and accessory bundles in one order
Important Information
- This kit supplies all interior sauna components. 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 must be performed by a licensed electrician in accordance with local building codes. Heater electrical requirements vary by model—confirm specifications with your electrician prior to purchase. High-output heaters (10–11KW) typically require a dedicated 240V circuit.
- Wall boards run horizontally by default. Because this room is 10 feet wide (exceeds 8 feet), an interior seam will be added where two boards meet to span the full width. This is standard practice and does not affect structural integrity.
- Backrests are shipped flat. On-site spacers can be fabricated to achieve an angled pitch if preferred.
- Product photos may show a glass wall for reference; your shipment includes an all-glass door as described.
- The Harvia Virta Combi includes a steam function. Steam sauna use requires additional plumbing for water supply—confirm requirements with your installer before ordering.
- This product is intended for indoor installation only.
Optional Heater Comparison
| Feature | Harvia Cilindro 11KW | Harvia Club 10KW | Harvia Virta 10.5KW | Harvia Virta Combi 10.5KW |
|---|---|---|---|---|
| Product Image |  |
 |
 |
 |
| Power Output | 11 KW | 10 KW | 10.5 KW | 10.5 KW |
| Brand | Harvia | Harvia | Harvia | Harvia |
| Control Type | WiFi Control | WiFi Control | WiFi Control | WiFi Control |
| WiFi Connectivity | Yes | Yes | Yes | Yes |
| Heater Stones Included | Yes | Yes | Yes | Yes |
| Railing Included | No | No | Yes | Yes |
| Combi Steam Function | No | No | No | Yes |
| Model Series | Cilindro | Club | Virta | Virta Combi |
| Remote Control | App-based via WiFi | App-based via WiFi | App-based via WiFi | App-based via WiFi |
Harvia Cilindro 11KW – WiFi
Harvia Club 10KW – WiFi
Harvia Virta 10.5KW – WiFi + Railing
Harvia Virta Combi 10.5KW – WiFi + Railing + Steam
Heater Key Differences
Power Output
- Harvia Cilindro: 11 KW — highest output in this lineup, suited for the largest sauna rooms
- Harvia Virta and Virta Combi: 10.5 KW — premium performance with railing and optional steam
- Harvia Club: 10 KW — commercial-grade floor-standing design for high-capacity use
Control & Connectivity
- All four models are WiFi-enabled with app-based remote control and scheduling
Railing & Steam
- Harvia Virta and Virta Combi both include a protective safety railing
- Harvia Virta Combi is the only model with an integrated Combi steam function—delivering both traditional dry sauna heat and steam in one unit (requires water supply plumbing)
Included Accessories
- All heater options include heater stones
Frequently Asked Questions
What does this kit include?
The kit includes all interior sauna components: foil vapor barrier, tongue & groove wall and ceiling boards, bench boards with supports, corner moldings, duckboard flooring, an all-glass door with wood trim, upper and lower vent grills, backrests, a headrest, a sauna bucket with liner and ladle, a thermometer, and a marine-grade vapor-proof light. Detailed installation instructions are also included.
What do I need to supply that is not in the kit?
You are responsible for the structural framing, insulation, electrical wiring, and exterior wall covering. A licensed electrician is required for heater wiring. High-output heaters (10–11KW) typically require a dedicated 240V circuit—confirm requirements with your electrician before ordering.
Can I order this kit without a heater?
Yes. Select "No Heater" in the Heater option at checkout. You can source and install a compatible heater separately, or contact our team for guidance on compatible models.
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 using a chemical-free process. This treatment improves dimensional stability and resistance to humidity and temperature fluctuations—properties that are important in a sauna environment. It also produces a warm, rich tone that complements the sauna aesthetic.
What ceiling height is required?
The recommended ceiling height is 8 feet, per manufacturer safety and clearance guidelines. If your space has a different ceiling height, please contact our support team before placing your order to discuss custom options.
What rough opening is needed for the door?
The included all-glass door requires a rough opening of 28″ × 80″. The door frame measures 27.2″ × 78.7″ (690 × 2000 mm) with a frame thickness of 1.65″ × 3.6″ (42 × 92 mm).
Will the wall boards span the full 10-foot width?
Because this room is 10 feet wide (exceeding the standard 8-foot board length), an interior seam will be added where two boards meet to span the full width. This is standard practice for rooms wider than 8 feet and does not affect structural integrity or appearance.
What is the Harvia Virta Combi and does it require extra plumbing?
The Harvia Virta Combi is a combination sauna heater and steam generator in one unit. It delivers both traditional dry sauna heat and steam. The steam function requires a water supply connection—confirm plumbing requirements with your installer before ordering this option.
Which heater should I choose?
All heater options are WiFi-enabled and include heater stones. The Cilindro 11KW offers the highest output. The Club 10KW is a commercial-grade floor-standing model. The Virta 10.5KW adds a protective safety railing. The Virta Combi 10.5KW includes both a railing and an integrated steam function. See the heater comparison chart above for a full side-by-side breakdown.
Can this kit be used for commercial installations?
This kit is suitable for light commercial use such as boutique fitness studios or wellness centers. For larger commercial projects or multi-room installations, contact our team for a custom consultation.
The Carbon Smart™ 7′ × 10′ × 8′ Indoor Sauna Kit is a complete, well-specified package for anyone ready to build a spacious, permanent sauna room at home or in a commercial setting. Select your accessory package and heater option above, and our team is available to answer any questions before you order.
Sauna use is a personal wellness practice. Consult a qualified healthcare provider before use if you have any medical conditions or concerns. This product is not intended to diagnose, treat, cure, or prevent any disease or medical condition.