BATHTUB
NEW SUSTUB DEBUT !
While some may be unfamiliar with stainless steel bathtubs today, they were once a common feature in Japanese homes. Several decades ago, many households adopted compact tubs with a stainless steel interior and an outer apron panel for concealment. This design was a standard choice for family baths at the time.
Our factory, now celebrating its 50th anniversary, has produced over one million bathtubs throughout its long history. However, as times changed, fiberglass-reinforced plastic (FRP) and other resin-based materials became the norm. These materials are cost-effective and offer a variety of shapes and colors, making them an attractive choice. Yet, when considering long-term durability and aging, resin is not always the ideal bathtub material.
Stainless steel, on the other hand, is highly resistant to rust and scratches, offering superior durability. Despite these qualities, its design remained largely unchanged, leaving it perceived as a relic of the past. However, even today, in many older homes, stainless steel bathtubs continue to serve their purpose without deterioration. Their deep, compact design allows for full immersion, offering a uniquely satisfying bathing experience—one that naturally makes you think, “Ah, this is a good soak.”
A newly built home is likely to be lived in for decades. Careful thought is given to its architecture, interiors, and comfort. Among these considerations, the bathroom is a place of daily relaxation and rejuvenation. What do we truly seek in a bathtub? What makes stainless steel a remarkable material?
With the desire to create something that remains beautiful and comfortable not just at the start, but for years to come, we embarked on a journey to reimagine and redefine the stainless steel bathtub.
New and a return to its origins
Our bathtubs are crafted with unwavering expertise, honed over decades. By combining this mastery with innovative textures and coatings, we have created a bathtub that transcends the conventional image of stainless steel tubs—introducing something entirely new.
Its name: SUSTUB (サスタブ).
Stainless steel is not only exceptionally durable for long-term use but also boasts an outstanding recyclability rate—nearly 100% reusable. It is a material that goes beyond single-generation consumption, offering a choice that connects to the future. As society reexamines the importance of sustainability, the value of stainless steel bathtubs is once again being recognized as a step toward a circular future.
Design
WHITE x SILVER is SUSTUB’s signature two-tone color. The pristine white interior enhances the clarity of the water, creating a visually striking bathing experience. The exterior, finished with a vibration technique, softens the shine while preserving the raw texture of the metal—resulting in a stunning contrast.
The CHARCOAL GRAY variant features a matte finish achieved through a blasting process that roughens the surface, revealing the natural color of stainless steel. Each finish is treated with a special coating that enhances the material’s inherent mineral-like hues, all without the use of artificial coloring.
Unlike cast or molded bathtubs, SUSTUB is crafted from a single stainless steel sheet. The process involves bending, welding, and meticulously polishing each seam—an intricate series of steps that ultimately result in a completely seamless form. Every detail is shaped by hand, ensuring a smooth, uninterrupted surface that highlights the beauty of stainless steel in its purest form.
A silky-smooth touch
The most essential aspect of a bathtub is how it feels against the skin. While SUSTUB’s design may appear sleek and minimalistic, every curve and edge has been meticulously refined down to the millimeter. From the gentle curvature of the interior and base to the precise width of the frame where your arms rest, every detail has been carefully considered through extensive prototyping.
The interior is crafted to provide a silky-smooth touch, while the outer edges are carefully hand-finished to ensure a comfortable, natural feel. Each surface is inspected and refined by skilled artisans to achieve the perfect balance of form and function.
(For those who require additional slip resistance, an optional water-drop embossed texture can be applied to the base.)
Size
The bathtub is designed to fit seamlessly into a standard one-tsubo (1㎡) bathroom space. In such cases, the apron panel is placed on one side. However, for larger bathrooms, a two-sided apron configuration can be chosen, allowing the rectangular form to be showcased beautifully, as seen in the photos. Since each bathtub is made to order, you can select the best configuration to suit your space.
The interior is designed with a gentle backrest incline, ensuring comfort while maintaining a balanced width and depth—deep enough for full immersion without feeling too shallow. When filled, the water envelops the body in a satisfying soak.
For solo bathing, the spacious design offers a luxurious, relaxing experience. The wider interior also accommodates bathing with a small child, allowing both to sit side by side with ample room to stretch their legs.
ZEROTECT®︎Coating
The interior and exterior surfaces of the bathtub are treated with a special anti-fouling coating, “ZEROTECT”®. Developed from ceramic glaze technology, ZEROTECT is a completely inorganic, ultra-hydrophilic coating that is both environmentally friendly and highly effective. Its self-cleaning properties are so powerful that even oil-based marker stains can be effortlessly rinsed away with just water. This innovation has gained recognition across various industries, including public facilities, and is increasingly being adopted for residential sinks, range hoods, dishware, and appliances.
For the first time, this advanced coating has been applied to a stainless steel bathtub, significantly enhancing both its design and functionality.
SUSTUB’s two-tone bathtub features a white ZEROTECT coating on the interior, providing a clean and refined aesthetic. The exterior is finished with a vibration-textured stainless steel surface, which enhances the natural expression of the metal. A transparent ZEROTECT coating is then applied on top, preserving its unique texture while offering superior stain resistance.
Typically, stainless steel surfaces are textured to enhance their natural appeal, but this also makes them more prone to fingerprints and smudges. However, with ZEROTECT, the bathtub achieves the perfect balance of metallic elegance and easy maintenance, ensuring a beautiful, long-lasting finish.
Exceptional Heat Retention
Among bathtub materials, stainless steel excels in heat retention. To further enhance its insulating properties, the underside of the bathtub is coated with high-performance thermal insulation foam (sprayed polyurethane). This additional layer helps maintain the water temperature for an extended period, ensuring a warm and comfortable bathing experience.
How to Order
As this product requires on-site installation, it is available exclusively for those considering new construction or renovation projects using traditional Japanese bathroom construction methods.
- The standard pre-set size can be installed in bathrooms of one tsubo (approx. 3.3㎡) or larger.
- Depending on the position of the plumbing (water supply and drainage), the orientation of the side panel (apron) will vary.
- Please consult with your architect or contractor and select the appropriate layout from the options below.
To place an order, please submit your request via the CONTACT form, specifying the layout and whether you require bottom embossing. After reviewing your request, we will issue a quotation and invoice.
We also accommodate custom orders beyond the standard options, including 3–4-sided aprons and special sizes. For bulk orders (e.g., for apartment complexes), we can provide customized quotes—please feel free to contact us for further details.
1面エプロン
ex）1坪（1616）
2面エプロン
ex）1.25坪（1620）
SUSTUB -WHITE x SILVER- Specifications
- Dimensions:
- Outer: 1400L × 800W × 430D mm
- Inner: 1300L × 700W × 410D mm
- Bottom: 1050L × 550W mm
- Material: SUS304 Stainless Steel
- Finish:
- Bathtub Interior: Zerotect White Coating
- Side Panels: Vibration Finish + Transparent Zerotect Coating
- Underside: Insulated with Sprayed Polyurethane Foam for Enhanced Heat Retention
- Pricing:
- Please inquire with your preferred size and apron configuration for a quotation.
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