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Finnish Sauna Builders

Custom Indoor Sauna Room - 3' x 4' x 8' - Finnish Sauna Builders

Custom Indoor Sauna Room - 3' x 4' x 8' - Finnish Sauna Builders

Regular price $6,534.10
Regular price Sale price $6,534.10
Sale Sold out
Wood type
Accessory Packages
Heater

Transform your home into a wellness retreat with the Finnish Sauna Builders Custom Indoor Sauna Room Kit. This complete sauna package includes everything you need to build an authentic Finnish sauna experience, whether you're a DIY enthusiast or a professional contractor.

Complete Sauna Kit - Ready for Your Space

Our custom indoor sauna kit arrives with all interior components precisely cut and tailored to your room dimensions. Simply provide the framing, insulation, electrical wiring, and exterior wall covering—we supply the rest. Building your dream sauna has never been easier or more affordable.

Premium Wood Options - Choose Your Perfect Finish

Select from three exceptional wood types, each offering distinctive benefits for your sauna interior:

Grade A Knot-Free Western Red Cedar

The classic choice for sauna enthusiasts. This premium softwood remains comfortably cool to the touch during sauna sessions and naturally resists moisture and decay. Enjoy its refined, knot-free appearance with beautiful color variations ranging from reddish to pinkish-brown tones, accented with darker bands and pale sapwood streaks.

Thermo Aspen/Alder

Experience the luxury of intense thermally modified wood, heat-treated at 419°F or higher. This advanced process creates a stunning deep, rich color while dramatically enhancing durability and dimensional stability. Perfect for those seeking a modern, sophisticated aesthetic with superior performance. Suitable for both indoor and outdoor applications.

Thermo Poplar

A thermally modified wood treated at approximately 374°F for optimal indoor sauna use. This medium modification delivers enhanced dimensional stability, improved resistance to humidity and temperature fluctuations, and a warm, rich tone—all achieved through a chemical-free process. Ideal for creating a naturally beautiful, long-lasting sauna environment.

Customizable Bench Configurations

Choose the bench layout that best fits your space and needs from our selection of configurations shown in the product images. Each configuration is designed to maximize comfort and optimize your sauna experience.

What's Included in Your Custom Sauna Kit:

  • Foil vapor barrier for proper moisture protection
  • Ergonomic backrests for comfortable relaxation
  • 1×4 tongue & groove boards (walls & ceiling) in your selected wood
  • Clear 1×4 bench boards with supports (20″ deep) in matching wood—custom-built to your chosen configuration
  • Corner moldings for walls, ceiling, and baseboards (matching wood)
  • All-glass sauna door with wood handles and trim
    • Frame: 27.2″ × 78.7″ (690 × 2000 mm)
    • Glass: 24.4″ × 77.3″ (620 × 1963 mm)
    • Frame thickness: 1.65″ × 3.6″ (42 × 92 mm)
    • Rough opening required: 28″ × 80″
  • Duckboard flooring for walk area (matching wood)
  • Upper and lower vent grills for proper air circulation
  • Traditional sauna bucket with liner and ladle
  • Sauna thermometer for temperature monitoring
  • Comfortable headrest
  • Marine-grade, wall-mount, vapor-proof sauna light
  • Detailed installation instructions for easy assembly

Important Installation Notes:

  • Recommended ceiling height is 8 feet per manufacturer safety and clearance guidelines. For custom ceiling heights, please contact our support team.

Perfect for Home or Commercial Use

Whether you're building a personal wellness sanctuary or outfitting a spa or gym, our DIY sauna kits deliver professional-quality materials at competitive prices.

Expert Support Available

Contact your Finnish Sauna Builders Specialist today for personalized guidance in creating the perfect sauna room for you and your family.

Note: Your sauna shipment will include an all-glass door, though some photos may display a glass wall for reference. Backrests are shipped flat; if you'd like an angled backrest, additional spacers can be easily created on-site to achieve your desired pitch.

Note: Wall boards run in the standard horizontal direction unless room width exceeds 8 ft; in such cases, an interior seam will be added where two boards meet to span the width.

Sauna Heater Comparison Chart

Feature Harvia KIP45B 4.5KW Harvia KIP45W 4.5KW HUUM Cliff Mini 3.5KW
Product Image Harvia KIP45B Sauna Heater Harvia KIP45W Sauna Heater HUUM Cliff Mini Sauna Heater
Power Output 4.5 KW 4.5 KW 3.5 KW
Cubic Feet Coverage 176 - 353 cu ft 176 - 353 cu ft 106 - 247 cu ft
Control Type Built-in Control WiFi Control WiFi Control
WiFi Connectivity ❌ No ✅ Yes ✅ Yes
Heater Stones Included ✅ Yes ✅ Yes ✅ Yes
Railing Included ❌ No ❌ No ✅ Yes
Brand Harvia Harvia HUUM
Model KIP45B KIP45W Cliff Mini
Remote Control Manual only App-based via WiFi App-based via WiFi

Harvia KIP45B 4.5KW

Harvia KIP45B Sauna Heater
Power Output
4.5 KW
Cubic Feet Coverage
176 - 353 cu ft
Control Type
Built-in Control
WiFi Connectivity
❌ No
Heater Stones Included
✅ Yes
Railing Included
❌ No
Brand
Harvia
Model
KIP45B
Remote Control
Manual only

Harvia KIP45W 4.5KW

Harvia KIP45W Sauna Heater
Power Output
4.5 KW
Cubic Feet Coverage
176 - 353 cu ft
Control Type
WiFi Control
WiFi Connectivity
✅ Yes
Heater Stones Included
✅ Yes
Railing Included
❌ No
Brand
Harvia
Model
KIP45W
Remote Control
App-based via WiFi

HUUM Cliff Mini 3.5KW

HUUM Cliff Mini Sauna Heater
Power Output
3.5 KW
Cubic Feet Coverage
106 - 247 cu ft
Control Type
WiFi Control
WiFi Connectivity
✅ Yes
Heater Stones Included
✅ Yes
Railing Included
✅ Yes
Brand
HUUM
Model
Cliff Mini
Remote Control
App-based via WiFi

Key Differences

Power & Heating Capacity:

  • Harvia models: 4.5 KW (suitable for 176-353 cubic feet)
  • HUUM Cliff Mini: 3.5 KW (suitable for 106-247 cubic feet)

Control & Connectivity:

  • KIP45B: Basic built-in control panel (no remote features)
  • KIP45W & Cliff Mini: WiFi-enabled for smartphone control and scheduling

Design & Accessories:

  • HUUM Cliff Mini is the only model that includes a protective railing
  • All models come with heater stones included
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