Custom Indoor Sauna Room - 6' x 10' x 8' - Finnish Sauna Builders — This custom-built Finnish sauna room measures 6' x 10' x 8', hand-crafted by Finnish Sauna Builders for premium home installation. Each unit is made-to-order to fit your specific dimensions and layout.

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 Cilindro PC90 9KW	Harvia Cilindro PC90E 9KW	Harvia Virta 9KW	EOS Cubo Avantgarde 9KW	EOS Mythos S35 9KW
Product Image
Power Output	9 KW	9 KW	9 KW	9 KW	9 KW
Brand	Harvia	Harvia	Harvia	EOS	EOS
Control Type	Built-in Control	WiFi Control	WiFi Control	WiFi Control	WiFi Control
WiFi Connectivity	❌ No	✅ Yes	✅ Yes	✅ Yes	✅ Yes
Heater Stones Included	✅ Yes	✅ Yes	✅ Yes	✅ Yes	✅ Yes
Railing Included	❌ No	❌ No	✅ Yes	❌ No	❌ No
Model Series	Cilindro Series	Cilindro Series	Virta Series	Cubo Avantgarde Series	Mythos Series
Model	PC90	PC90E	Virta	Cubo Avantgarde	Mythos S35
Remote Control	Manual only	App-based via WiFi	App-based via WiFi	App-based via WiFi	App-based via WiFi

Harvia Cilindro PC90 9KW Built-in Control

Power Output

9 KW

Brand

Harvia

Control Type

Built-in Control

WiFi Connectivity

❌ No

Heater Stones Included

✅ Yes

Railing Included

❌ No

Model Series

Cilindro Series

Model

PC90

Remote Control

Manual only

Harvia Cilindro PC90E 9KW WiFi

Power Output

9 KW

Brand

Harvia

Control Type

WiFi Control

WiFi Connectivity

✅ Yes

Heater Stones Included

✅ Yes

Railing Included

❌ No

Model Series

Cilindro Series

Model

PC90E

Remote Control

App-based via WiFi

Harvia Virta 9KW WiFi with Railing

Power Output

9 KW

Brand

Harvia

Control Type

WiFi Control

WiFi Connectivity

✅ Yes

Heater Stones Included

✅ Yes

Railing Included

✅ Yes

Model Series

Virta Series

Model

Virta

Remote Control

App-based via WiFi

EOS Cubo Avantgarde 9KW WiFi

Power Output

9 KW

Brand

EOS

Control Type

WiFi Control

WiFi Connectivity

✅ Yes

Heater Stones Included

✅ Yes

Railing Included

❌ No

Model Series

Cubo Avantgarde Series

Model

Cubo Avantgarde

Remote Control

App-based via WiFi

EOS Mythos S35 9KW WiFi

Power Output

9 KW

Brand

EOS

Control Type

WiFi Control

WiFi Connectivity

✅ Yes

Heater Stones Included

✅ Yes

Railing Included

❌ No

Model Series

Mythos Series

Model

Mythos S35

Remote Control

App-based via WiFi

Key Differences

Power & Heating Capacity:

• All models: 9 KW power output for powerful heating performance in larger sauna rooms

Brands:

• Harvia (Finnish): Cilindro PC90, Cilindro PC90E, Virta — trusted Finnish heritage brand with decades of sauna expertise
• EOS (German): Cubo Avantgarde, Mythos S35 — premium German engineering with innovative design aesthetics

Control & Connectivity:

• Cilindro PC90: Basic built-in control panel only — no remote or app features
• Cilindro PC90E, Virta, EOS Cubo Avantgarde & EOS Mythos S35: WiFi-enabled for smartphone control and scheduling

Design & Model Series:

• Cilindro Series: Iconic cylindrical design with large stone capacity, available in standard (PC90) and WiFi-enabled (PC90E) versions
• Virta Series: Premium Harvia model with WiFi control and included protective safety railing
• EOS Cubo Avantgarde: Bold cubic form with WiFi control and a striking modern aesthetic
• EOS Mythos S35: Sleek, minimalist German design with WiFi connectivity and high stone capacity

Included Accessories:

• All models come with heater stones included
• Harvia Virta is the only model in this lineup that includes a protective safety railing

Shipping Information

Once you place an order with Peak Flow Fitness, you'll receive a confirmation email from our team. Have questions? Text or call us at 646-921-5221 or email support@peakflowfitness.com.

Processing time: Most orders are processed within 1–3 business days.

Shipping method: Smaller items ship via UPS, FedEx, or USPS. Large equipment — including saunas, cold plunges, massage chairs, and gym machines — ships via LTL freight with curbside delivery. Our freight carrier will contact you to schedule your delivery appointment.

Transit time: Most orders arrive within 5–10 business days after processing, depending on item size and your location. Freight shipments may take longer and are scheduled with you in advance.

Where we ship: We currently ship within the continental United States. Enjoy free shipping on orders over $999 (exclusions apply).

Peak Flow Fitness guarantees the lowest eligible online price on it's products.

If you find a lower price for any products on our store, we pice match it. In order to be eligible, you must provide proof - whether a screenshot, invoice, email, etc. of the lower offer.

Policy

We work very hard to ensure that we offer the absolute best prices online. If you find another online store that offers a lower price than us, please let us know and we will refund your original payment for the difference. We want you to feel confident that you are getting the absolute best price for the product you are ordering.

Our 100% Price Match Guarantee has some limitations:• You must purchase the item from our website before requesting your Price Match Guarantee
• Promotions such as rebates and buy one, get one free offers are not eligible
• The item must be in stock on the competitors website
• The competitor must be an online store, they may not have a retail location
• The website can not be a discounter or auction website (ie; eBay, overstock, etc.)
• Refund requests EXCLUDE special once-a-year promotions such as Black Friday/Cyber Monday.
• The competitor must be an Authorized Retailer of the product in question
• The Price Match Guarantee includes the item price and the shipping charges, it excludes sales tax.

*Certain exceptions may apply.Peak Flow Fitness strives to give its customers the lowest price allowed by its manufacturers. We want you to have the best value and the best deal which is why we always offer the best sales and discounts. Keep checking our website for new deals and subscribe to our social media accounts to get the latest that we are offering.

Return Policy

Returns

Your online shopping experience should be fun and easy, so don't be afraid to try some new things! If an item arrives broken or damaged, return it for a full refund within 30 days of your delivery date in its original condition and packaging. For an item to be eligible for a return, it must be unused and in the condition you received it in. 

*PLEASE BE AWARE THAT SOME ITEMS ARE SUBJECT TO A 15% MINIMUM RESTOCKING FEE UPON RETURN* (Click on the "Free Return '' option box at shipping checkout to avoid a restocking fee. Please note that the restocking fee does not include the return shipping costs associated with the product)

Packages that arrive with the incorrect product or are damaged are not subject to a 15% restocking fee. If there was any error on our end we will take care of it. Contact us with any additional questions or inquiries at 646-921-5221.

Missing Parts?

If for some reason your order arrives and is missing parts, please contact us immediately at 646-921-5221 and we will send out a replacement order for your missing part(s) immediately. 

Shipping

PeakFlowFitness will not cover the cost of return shipping. Shipping costs are non-refundable and are the responsibility of the customer, unless there was an error on our part. You will always have the option to request a return label and one will be provided for all your orders, but please note the cost of the return label can be deducted from your refund. 

Please reach out to 646-921-5221 to start your return!

To begin a return, please include a receipt or any other proof of purchase in your email. In addition, label the subject line of your message  "RETURN - ORDER #" so we can work on your return right away. 

It is also very important you state the reason for your return as well as any evidence of the product that may be needed in the return process, such as pictures or videos.

We asked that you contact us first and file a return so we can properly track the items before you return items to the manufacturer.

We use a warehouse to handle our returns. If a product was returned and we were not contacted about the return, it cannot be verified, therefore, there will be no refund. NO EXCEPTIONS! We ask that you please reach out to us and submit a return claim. 

There are situations where only partial refunds are granted (if applicable)

Books with obvious signs of use or wear and tear.

CD, DVD, VHS tape, software, video game, cassette tape, or vinyl record that have been opened or used. 

Any item that is not in its original condition, is damaged or missing pieces for reasons not due to our error. 

I PROVIDED THE WRONG ADDRESS

If you provided us with an incorrect address, or have misspelled information please do not worry. Simply reply to the order confirmation email you received and send us the correct information. We do ask that you notify us immediately via 646-921-5221. It is important that any mistakes made are corrected within 24 hours, before the item is shipped out. 

ITEM IS DAMAGED UPON ARRIVAL

We pride ourselves on taking care of each order that is sent out to our customers. However, accidents still do occur due to postal service mistreatment. Please follow these instructions if your item arrived damaged:

Please contact us with:

    - Your order number.

    - A picture or video of the damaged product.

Once your item is reviewed and processed, we will issue you a replacement item sent to you free-of-charge. In some cases we may also provide a shipping label to return the damaged item. If no label is provided, feel free to keep the item.

PLEASE NOTE: IF A PACKAGE ARRIVES DAMAGED. WE CAN REPLACE THE ORDER WITH NO ADDITIONAL COST, BUT IF YOU CHOOSE TO NOT GO AHEAD WITH A REPLACEMENT THE TRANSACTION WILL BE TREATED AS A RETURN AND ADDITIONAL FEES MAY INCUR. 

WHAT ARE MY PAYMENT OPTIONS?

We currently accept Stripe, Paypal, AMEX, Discovery, Mastercard, Visa or Paypal. Please contact us with any questions regarding payment options. 

I WANT TO EXCHANGE MY ORDER

If for some reason you are unsatisfied with your order and want to exchange it for a different make or model, please email us at support@peakflowfitness.com and we will issue a return label. The new product will then be shipped out in 1-2 business days. 

CAN I CANCEL MY ORDER?

Of course! You can cancel an order with no penalties. We do ask that you cancel your order within 24 hours of creating it or the cancellation may not be applied. If the item has already been shipped, please email support@peakflowfitness.com. Please send us an email with the subject line “CANCEL". We can cancel any orders that are not processed. Please reach out to us as soon as possible if you do decide to change your mind. Once an order is processed, there cannot be any cancellations. All cancellations are subject to a credit card CC fee of 3.5%.

Refunds (if applicable)

All refunds, unless otherwise specified, must be sent to the return address specified below.

Once your return item reaches our warehouse and has been inspected and reviewed, your refund / return will then be verified. It usually takes 1 business day from when your package arrived for us to finalize your return. Once approved, your refund amount will be processed back to your original payment method. Please also note that it may take up to 5-10 business days for the refund to appear back in your account after we have processed it in our system. 

Late or missing refunds (if applicable)

If your refund has yet to be refunded to your original payment, please don't worry. First, we ask that you check with your bank account to see if the refund transaction is pending. A lot of times your bank or payment provider may have a processing time for refunds, so please allow 5-10 business days after we have refunded you on our system for it to appear in your payment method. We will always be happy to walk you through every step of the way!

Return Address:

1923 McDonald Avenue SUITE # 1022

Brooklyn, NY 11223

United States

STILL HAVE A QUESTION?

If we were unable to answer all of your questions, please do not hesitate to contact us at  646-921-5221.