{"product_id":"carbon-smart-indoor-sauna-kit-4x5x8-thermo-poplar","title":"Carbon Smart Indoor Sauna Kit – 4' x 5' x 8' | Thermo Poplar","description":"\u003cdiv class=\"iwl-sauna-page\"\u003e\n\n\u003c!-- ===== INTRO ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-intro\"\u003e\n\u003cp\u003eThe Carbon Smart™ Indoor Sauna Kit in the 4 ft × 5 ft × 8 ft configuration offers a practical middle ground between the compact 4×4 and the larger 4×6 sizes—providing enough floor space for comfortable single-user use or occasional two-person sessions, while still fitting in spaces where a full-size sauna room is not practical. The kit ships as a complete interior package: precision-cut Thermo Poplar wall and ceiling boards, all-glass door, bench components, lighting, ventilation, and all finishing accessories.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== WHY CUSTOMERS CHOOSE THIS ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-why-choose\"\u003e\n\u003ch2\u003eWhy Customers Choose This Kit\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e4 x 5 footprint offers more usable floor space than the 4 x 4 while remaining compact\u003c\/li\u003e\n\u003cli\u003eComplete interior package—walls, ceiling, benches, door, lighting, and accessories included\u003c\/li\u003e\n\u003cli\u003eThermo Poplar wood is thermally modified without chemicals for lasting dimensional stability\u003c\/li\u003e\n\u003cli\u003ePrecision-cut components reduce installation time and on-site waste\u003c\/li\u003e\n\u003cli\u003eRight-sized heater options (3.5 KW and 4.5 KW) matched to the interior volume\u003c\/li\u003e\n\u003cli\u003eOptional accessory packages let you customize the finish level\u003c\/li\u003e\n\u003cli\u003eSuitable for both residential and light commercial installations\u003c\/li\u003e\n\u003cli\u003eDetailed installation instructions included\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== PRODUCT HIGHLIGHTS ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-highlights\"\u003e\n\u003ch2\u003eProduct Highlights\u003c\/h2\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003ePractical 4 x 5 Floor Plan\u003c\/h3\u003e\n\u003cp\u003eThe 4×5×8 configuration provides 20 square feet of interior floor space—enough for a comfortable single-user layout with room to move, or a compact two-person bench arrangement. It fits in spaces where a 4×6 or larger room is not available.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003eThermo Poplar Interior\u003c\/h3\u003e\n\u003cp\u003eAll 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 improves dimensional stability and resistance to humidity without the use of chemicals.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003eAll-Glass Sauna Door\u003c\/h3\u003e\n\u003cp\u003eThe 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″.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003eFoil Vapor Barrier\u003c\/h3\u003e\n\u003cp\u003eA foil vapor barrier is included to protect the wall structure from moisture migration—an essential component for long-term sauna performance.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003eVentilation System\u003c\/h3\u003e\n\u003cp\u003eUpper and lower vent grills are included to support proper air circulation throughout the sauna session.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003eMarine-Grade Vapor-Proof Lighting\u003c\/h3\u003e\n\u003cp\u003eA wall-mount, marine-grade, vapor-proof sauna light is included—rated for the high-heat, high-humidity sauna environment.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-highlight-item\"\u003e\n\u003ch3\u003eRight-Sized Heater Options\u003c\/h3\u003e\n\u003cp\u003eTwo WiFi-enabled heater options are available at checkout—the Harvia KIP45W (4.5 KW) and the HUUM Cliff Mini (3.5 KW with railing)—both sized appropriately for the 4×5 interior volume. Both include sauna stones.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== WHAT'S INCLUDED ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-included\"\u003e\n\u003ch2\u003eWhat's Included\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eFoil vapor barrier\u003c\/li\u003e\n\u003cli\u003e1×4 tongue-and-groove wall and ceiling boards (Thermo Poplar)\u003c\/li\u003e\n\u003cli\u003eClear 1×4 bench boards with supports, 20″ deep (Thermo Poplar, custom-built to your chosen configuration)\u003c\/li\u003e\n\u003cli\u003eCorner moldings for walls, ceiling, and baseboards (Thermo Poplar)\u003c\/li\u003e\n\u003cli\u003eErgonomic backrests\u003c\/li\u003e\n\u003cli\u003eAll-glass sauna door with wood handles and trim (frame: 27.2″ × 78.7″; rough opening: 28″ × 80″)\u003c\/li\u003e\n\u003cli\u003eDuckboard flooring for walk area (Thermo Poplar)\u003c\/li\u003e\n\u003cli\u003eUpper and lower vent grills\u003c\/li\u003e\n\u003cli\u003eTraditional sauna bucket with liner and ladle\u003c\/li\u003e\n\u003cli\u003eSauna thermometer\u003c\/li\u003e\n\u003cli\u003eHeadrest\u003c\/li\u003e\n\u003cli\u003eMarine-grade, wall-mount, vapor-proof sauna light\u003c\/li\u003e\n\u003cli\u003eDetailed installation instructions\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eNote:\u003c\/strong\u003e Some product photos may show a glass wall for reference; your shipment includes an all-glass door. Backrests are shipped flat; angled pitch can be achieved on-site with spacers. Wall boards run horizontally by default; rooms wider than 8 ft will include an interior seam where boards meet.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== SPECIFICATIONS ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-specs\"\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable class=\"iwl-specs-table\"\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003cth\u003eInterior Dimensions\u003c\/th\u003e\n\u003ctd\u003e4 ft × 5 ft × 8 ft\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eInterior Floor Area\u003c\/th\u003e\n\u003ctd\u003e20 sq ft\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWood Species\u003c\/th\u003e\n\u003ctd\u003eThermo Poplar (thermally modified)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eModification Temperature\u003c\/th\u003e\n\u003ctd\u003eApproximately 374°F (chemical-free process)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eWall \/ Ceiling Profile\u003c\/th\u003e\n\u003ctd\u003e1×4 tongue-and-groove\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eBench Depth\u003c\/th\u003e\n\u003ctd\u003e20 inches\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eDoor Frame Dimensions\u003c\/th\u003e\n\u003ctd\u003e27.2″ × 78.7″ (690 × 2000 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eDoor Glass Dimensions\u003c\/th\u003e\n\u003ctd\u003e24.4″ × 77.3″ (620 × 1963 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eDoor Frame Thickness\u003c\/th\u003e\n\u003ctd\u003e1.65″ × 3.6″ (42 × 92 mm)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eRough Opening Required\u003c\/th\u003e\n\u003ctd\u003e28″ × 80″\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eRecommended Ceiling Height\u003c\/th\u003e\n\u003ctd\u003e8 feet\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eHeater Options\u003c\/th\u003e\n\u003ctd\u003eNo Heater, Harvia KIP45W 4.5KW WiFi, or HUUM Cliff Mini 3.5KW WiFi\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eAccessory Packages\u003c\/th\u003e\n\u003ctd\u003eNo Accessories, Bench Skirting, LED Under Bench Lighting, Luxury Package (Skirting + LED)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003cth\u003eShipping Weight (approx.)\u003c\/th\u003e\n\u003ctd\u003e800 lbs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== HEATER COMPARISON ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-heater-comparison\"\u003e\n\u003ch2\u003eSauna Heater Comparison\u003c\/h2\u003e\n\n\u003c!-- Desktop Table --\u003e\n\u003cdiv class=\"sauna-comparison-table-wrapper\"\u003e\n\u003ctable class=\"sauna-comparison-table\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eFeature\u003c\/th\u003e\n\u003cth\u003eHarvia KIP45W 4.5KW\u003c\/th\u003e\n\u003cth\u003eHUUM Cliff Mini 3.5KW\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eProduct Image\u003c\/td\u003e\n\u003ctd class=\"sauna-heater-image-cell\"\u003e\u003cimg alt=\"Harvia KIP45W Sauna Heater\" class=\"sauna-heater-image\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0582\/6386\/3453\/files\/Harvia_KIP45W.webp?v=1770155911\"\u003e\u003c\/td\u003e\n\u003ctd class=\"sauna-heater-image-cell\"\u003e\u003cimg alt=\"HUUM Cliff Mini Sauna Heater\" class=\"sauna-heater-image\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0582\/6386\/3453\/files\/Huum_Cliff_3-5kw.webp?v=1770155911\"\u003e\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003ePower Output\u003c\/td\u003e\n\u003ctd\u003e4.5 KW\u003c\/td\u003e\n\u003ctd\u003e3.5 KW\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eCoverage (cubic feet)\u003c\/td\u003e\n\u003ctd\u003e176–353 cu ft\u003c\/td\u003e\n\u003ctd\u003e106–247 cu ft\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eControl Type\u003c\/td\u003e\n\u003ctd\u003eWiFi Control\u003c\/td\u003e\n\u003ctd\u003eWiFi Control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eWiFi Connectivity\u003c\/td\u003e\n\u003ctd class=\"sauna-check-yes\"\u003eYes\u003c\/td\u003e\n\u003ctd class=\"sauna-check-yes\"\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eHeater Stones Included\u003c\/td\u003e\n\u003ctd class=\"sauna-check-yes\"\u003eYes\u003c\/td\u003e\n\u003ctd class=\"sauna-check-yes\"\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eRailing Included\u003c\/td\u003e\n\u003ctd class=\"sauna-check-no\"\u003eNo\u003c\/td\u003e\n\u003ctd class=\"sauna-check-yes\"\u003eYes\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eBrand\u003c\/td\u003e\n\u003ctd\u003eHarvia\u003c\/td\u003e\n\u003ctd\u003eHUUM\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eModel\u003c\/td\u003e\n\u003ctd\u003eKIP45W\u003c\/td\u003e\n\u003ctd\u003eCliff Mini\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd class=\"sauna-feature-label\"\u003eRemote Control\u003c\/td\u003e\n\u003ctd\u003eApp-based via WiFi\u003c\/td\u003e\n\u003ctd\u003eApp-based via WiFi\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/div\u003e\n\n\u003c!-- Mobile Cards --\u003e\n\u003cdiv class=\"sauna-mobile-cards\"\u003e\n\u003cdiv class=\"sauna-mobile-card\"\u003e\n\u003ch3 class=\"sauna-mobile-card-title\"\u003eHarvia KIP45W 4.5KW WiFi\u003c\/h3\u003e\n\u003cdiv class=\"sauna-mobile-card-image\"\u003e\u003cimg alt=\"Harvia KIP45W Sauna Heater\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0582\/6386\/3453\/files\/Harvia_KIP45W.webp?v=1770155911\"\u003e\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003ePower\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value\"\u003e4.5 KW\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eCoverage\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value\"\u003e176–353 cu ft\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eControl\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value\"\u003eWiFi \/ App\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eStones\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value sauna-check-yes\"\u003eIncluded\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eRailing\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value sauna-check-no\"\u003eNot included\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-card\"\u003e\n\u003ch3 class=\"sauna-mobile-card-title\"\u003eHUUM Cliff Mini 3.5KW WiFi\u003c\/h3\u003e\n\u003cdiv class=\"sauna-mobile-card-image\"\u003e\u003cimg alt=\"HUUM Cliff Mini Sauna Heater\" src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0582\/6386\/3453\/files\/Huum_Cliff_3-5kw.webp?v=1770155911\"\u003e\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003ePower\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value\"\u003e3.5 KW\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eCoverage\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value\"\u003e106–247 cu ft\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eControl\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value\"\u003eWiFi \/ App\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eStones\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value sauna-check-yes\"\u003eIncluded\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-row\"\u003e\n\u003cdiv class=\"sauna-mobile-feature-label\"\u003eRailing\u003c\/div\u003e\n\u003cdiv class=\"sauna-mobile-feature-value sauna-check-yes\"\u003eIncluded\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003cdiv class=\"iwl-heater-key-differences\"\u003e\n\u003ch3\u003eKey Differences at a Glance\u003c\/h3\u003e\n\u003cul\u003e\n\u003cli\u003eBoth heater options are WiFi-enabled and controllable via smartphone app\u003c\/li\u003e\n\u003cli\u003eBoth include sauna stones\u003c\/li\u003e\n\u003cli\u003eHarvia KIP45W: 4.5 KW output, compact wall-mount profile, no railing\u003c\/li\u003e\n\u003cli\u003eHUUM Cliff Mini: 3.5 KW output, modern design, includes a protective railing\u003c\/li\u003e\n\u003cli\u003eThe 4×5×8 interior volume (160 cu ft) is within the rated coverage range of both heater options\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== IDEAL FOR ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-ideal-for\"\u003e\n\u003ch2\u003eIdeal For\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eSingle-user installations where a 4×4 feels too tight but a 4×6 is too large for the available space\u003c\/li\u003e\n\u003cli\u003eOccasional two-person use with a compact bench layout\u003c\/li\u003e\n\u003cli\u003eHomeowners building a dedicated sauna room in a basement, garage, or spare room with a moderate footprint\u003c\/li\u003e\n\u003cli\u003eDIY builders and professional contractors looking for precision-cut, ready-to-install components\u003c\/li\u003e\n\u003cli\u003eResidential wellness spaces and personal retreats\u003c\/li\u003e\n\u003cli\u003eLight commercial applications where a mid-size compact sauna room is needed\u003c\/li\u003e\n\u003cli\u003eBuyers who want to select their own heater or add one later\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== IMPORTANT INFORMATION ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-important-info\"\u003e\n\u003ch2\u003eImportant Information\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eFraming, insulation, electrical wiring, and exterior wall covering are not included\u003c\/strong\u003e and must be supplied by the installer.\u003c\/li\u003e\n\u003cli\u003eRecommended ceiling height is 8 feet per manufacturer safety and clearance guidelines. For custom ceiling heights, contact our support team before ordering.\u003c\/li\u003e\n\u003cli\u003eElectric sauna heaters require a dedicated electrical circuit. Consult a licensed electrician to confirm your installation meets local electrical code requirements.\u003c\/li\u003e\n\u003cli\u003eAll heater installations should comply with the manufacturer's minimum clearance specifications and applicable local building codes.\u003c\/li\u003e\n\u003cli\u003eVerify that your chosen heater's rated coverage range is appropriate for your finished interior volume, accounting for insulation quality and ceiling height.\u003c\/li\u003e\n\u003cli\u003eThis kit is designed for indoor use only. Do not install in unheated or uninsulated spaces without consulting a qualified contractor.\u003c\/li\u003e\n\u003cli\u003eSauna use is not recommended for individuals with certain medical conditions. Consult a qualified healthcare provider before use if you have any health concerns.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== FAQ ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-faq\"\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eWhat does this kit include?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eThe kit includes all interior sauna components: tongue-and-groove wall and ceiling boards, bench boards and supports, corner moldings, backrests, duckboard flooring, an all-glass door with wood handles and trim, upper and lower vent grills, a foil vapor barrier, a sauna bucket with liner and ladle, a thermometer, a headrest, and a marine-grade vapor-proof light. Detailed installation instructions are also included.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eWhat do I need to supply that is not included?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eYou will need to supply the structural framing, insulation, electrical wiring, and exterior wall covering. If you select a heater option, a licensed electrician will need to install a dedicated electrical circuit sized to the heater's specifications.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eHow does the 4 x 5 size compare to the 4 x 4 and 4 x 6?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eThe 4×5 provides 20 square feet of floor space—one foot more length than the 4×4 (16 sq ft) and one foot less than the 4×6 (24 sq ft). It is a practical choice when you want more room than the 4×4 but your available space or budget does not accommodate the 4×6.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eWhich heater is better for this size—the Harvia KIP45W or the HUUM Cliff Mini?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eBoth heaters are sized appropriately for the 4×5×8 interior volume (160 cu ft). The Harvia KIP45W offers 4.5 KW of output and a compact wall-mount profile. The HUUM Cliff Mini offers 3.5 KW and includes a protective railing. Both are WiFi-enabled and include sauna stones. The choice depends on your preferred output level and whether you want the railing included.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eCan I order this kit without a heater and add one later?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eYes. Select \"No Heater\" at checkout to receive the full interior kit without a heater. You can source and install a compatible heater separately at any time.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eWhat is Thermo Poplar and why is it used?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eThermo Poplar is a sustainably sourced wood that has been thermally modified at approximately 374°F. The heat treatment improves the wood's dimensional stability and resistance to humidity and temperature fluctuations—without the use of chemicals. It is well suited for the high-heat, high-humidity environment of a sauna interior.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eWhat rough opening is required for the door?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eThe all-glass door requires a rough opening of 28″ × 80″. The door frame dimensions are 27.2″ × 78.7″ (690 × 2000 mm).\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eCan I request a custom ceiling height?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eThe standard kit is designed for an 8-foot ceiling height per manufacturer safety and clearance guidelines. If your space requires a different ceiling height, please contact our support team before placing your order.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003cdetails class=\"iwl-faq-item\"\u003e\n\u003csummary class=\"iwl-faq-question\"\u003eIs this kit suitable for commercial use?\u003c\/summary\u003e\n\u003cdiv class=\"iwl-faq-answer\"\u003e\n\u003cp\u003eYes. The Carbon Smart™ kit is suitable for light commercial applications. For high-traffic commercial environments, contact our team to discuss the appropriate size configuration.\u003c\/p\u003e\n\u003c\/div\u003e\n\u003c\/details\u003e\n\n\u003c\/div\u003e\n\n\u003c!-- ===== CLOSING ===== --\u003e\n\u003cdiv class=\"iwl-section iwl-closing\"\u003e\n\u003cp\u003eThe Carbon Smart™ 4 × 5 × 8 Indoor Sauna Kit is a complete, well-specified package that fits where larger sizes cannot—without compromising on materials or finish quality. Select your accessory package and heater option above to configure your kit and place your order.\u003c\/p\u003e\n\u003c\/div\u003e\n\n\u003c!-- ===== HEALTH DISCLAIMER ===== --\u003e\n\u003cp style=\"text-align: center; font-size: 0.8em; color: #888; margin-top: 2rem;\"\u003eSauna use may not be appropriate for everyone. Consult a qualified healthcare provider before use if you have any medical conditions or health concerns. This product is not intended to diagnose, treat, cure, or prevent any disease or medical condition.\u003c\/p\u003e\n\n\u003c!-- ===== FAQ SCHEMA ===== --\u003e\n\u003cscript type=\"application\/ld+json\"\u003e\n{\n  \"@context\": \"https:\/\/schema.org\",\n  \"@type\": \"FAQPage\",\n  \"mainEntity\": [\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What does this kit include?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The kit includes all interior sauna components: tongue-and-groove wall and ceiling boards, bench boards and supports, corner moldings, backrests, duckboard flooring, an all-glass door with wood handles and trim, upper and lower vent grills, a foil vapor barrier, a sauna bucket with liner and ladle, a thermometer, a headrest, and a marine-grade vapor-proof light. Detailed installation instructions are also included.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What do I need to supply that is not included?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"You will need to supply the structural framing, insulation, electrical wiring, and exterior wall covering. If you select a heater option, a licensed electrician will need to install a dedicated electrical circuit sized to the heater's specifications.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"How does the 4 x 5 size compare to the 4 x 4 and 4 x 6?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The 4x5 provides 20 square feet of floor space—one foot more length than the 4x4 (16 sq ft) and one foot less than the 4x6 (24 sq ft). It is a practical choice when you want more room than the 4x4 but your available space or budget does not accommodate the 4x6.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Which heater is better for this size—the Harvia KIP45W or the HUUM Cliff Mini?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Both heaters are sized appropriately for the 4x5x8 interior volume (160 cu ft). The Harvia KIP45W offers 4.5 KW and a compact wall-mount profile. The HUUM Cliff Mini offers 3.5 KW and includes a protective railing. Both are WiFi-enabled and include sauna stones.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I order this kit without a heater and add one later?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. Select 'No Heater' at checkout to receive the full interior kit without a heater. You can source and install a compatible heater separately at any time.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What is Thermo Poplar and why is it used?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Thermo Poplar is a sustainably sourced wood thermally modified at approximately 374 degrees Fahrenheit. The heat treatment improves dimensional stability and resistance to humidity without chemicals, making it well suited for the high-heat, high-humidity sauna environment.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"What rough opening is required for the door?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The all-glass door requires a rough opening of 28 inches by 80 inches. The door frame dimensions are 27.2 inches by 78.7 inches (690 x 2000 mm).\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Can I request a custom ceiling height?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"The standard kit is designed for an 8-foot ceiling height. If your space requires a different ceiling height, please contact our support team before placing your order.\"\n      }\n    },\n    {\n      \"@type\": \"Question\",\n      \"name\": \"Is this kit suitable for commercial use?\",\n      \"acceptedAnswer\": {\n        \"@type\": \"Answer\",\n        \"text\": \"Yes. The Carbon Smart kit is suitable for light commercial applications. For high-traffic commercial environments, contact our team to discuss the appropriate size configuration.\"\n      }\n    }\n  ]\n}\n\u003c\/script\u003e\n\n\u003c\/div\u003e","brand":"Finnish Sauna Builders","offers":[{"title":"Thermo Poplar \/ No Accessories \/ No Heater","offer_id":50263947182319,"sku":"sku-48203075191025","price":6323.9,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ No Accessories \/ Harvia KIP45W 4.5KW WiFi with Heater Stones","offer_id":50263947215087,"sku":"sku-48203075223793","price":8584.9,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ No Accessories \/ HUUM Cliff Mini 3.5KW WiFi with Heater Stones and Railing","offer_id":50263947247855,"sku":"sku-48203075256561","price":9970.9,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ Bench Skirting \/ No Heater","offer_id":50263947280623,"sku":"sku-48203075289329","price":6745.4,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ Bench Skirting \/ Harvia KIP45W 4.5KW WiFi with Heater Stones","offer_id":50263947313391,"sku":"thermo-3-4-23","price":9006.4,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ Bench Skirting \/ HUUM Cliff Mini 3.5KW WiFi with Heater Stones and Railing","offer_id":50263947346159,"sku":"thermo-3-4-26","price":10392.4,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ LED Under Bench Lighting \/ No Heater","offer_id":50263947378927,"sku":"sku-48203075387633","price":7012.9,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ LED Under Bench Lighting \/ Harvia KIP45W 4.5KW WiFi with Heater Stones","offer_id":50263947411695,"sku":"thermo-3-4-24","price":9273.9,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ LED Under Bench Lighting \/ HUUM Cliff Mini 3.5KW WiFi with Heater Stones and Railing","offer_id":50263947444463,"sku":"thermo-3-4-27","price":10659.9,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ Luxury Package: Skirting + LED Under Bench Lighting \/ No Heater","offer_id":50263947477231,"sku":"sku-48203075485937","price":7434.4,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ Luxury Package: Skirting + LED Under Bench Lighting \/ Harvia KIP45W 4.5KW WiFi with Heater Stones","offer_id":50263947509999,"sku":"thermo-3-4-25","price":9695.4,"currency_code":"USD","in_stock":true},{"title":"Thermo Poplar \/ Luxury Package: Skirting + LED Under Bench Lighting \/ HUUM Cliff Mini 3.5KW WiFi with Heater Stones and Railing","offer_id":50263947542767,"sku":"thermo-3-4-28","price":11081.4,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0808\/7568\/4079\/files\/Thermo_Poplar_Indoor_Sauna_Kit.webp?v=1785267058","url":"https:\/\/intentionalwellnesslab.com\/products\/carbon-smart-indoor-sauna-kit-4x5x8-thermo-poplar","provider":"Intentional Wellness Lab","version":"1.0","type":"link"}