Stainless Watershapers (Part II)

Stainless-steel vessels have grown dramatically in popularity over the past 20 years, observes Mark Holden and Jeff Freeman. That rise has created both opportunities and challenges: while stainless offers remarkable advantages, missteps in design or fabrication can lead to failures, costly remediation, or even litigation. Understanding both sides of the equation is essential for watershapers working in today’s stainless marketplace.

By Mark Holden & Jeff Freeman

In our previous article in this two-part series, we outlined the basics of watershaping with stainless steel vessels. Here, we take the next step — reinforcing the practices and perspectives that improve outcomes and help guarantee success in your stainless endeavors.

Through discussions with Joshua Albertson, an experienced sales engineer with Natare Pools — an employee-owned, 50-person firm based in Indianapolis that makes stainless steel pools, spas, bulkheads, filters and other products — we’ve gained valuable insight into the stainless-steel world, and especially what fellow watershapers should know about these products.

While watershapers sometimes see stainless pools as a novelty, Albertson points out that the material has steadily grown in use and acceptance, adding, “there is a very elaborate network of professionals who design and fabricate stainless steel into all forms of watershapes.”

In his role at Natare, Albertson has gained a unique and detailed perspective on what is needed to make the most of the advantages offered by stainless steel pools, and what watershapers should keep in mind on projects that include them.

Roles, Responsibilities, and Collaboration

Albertson routinely works with a variety of involved professionals and is able to speak with designers, builders and end-users on a detailed level to obtain a high-quality watershape. His definition of these contacts are mostly watershapers in the contracting trades with pool builders being the predominant source, with general contractors and then architects falling in behind.

The majority of projects using stainless steel tend to be over-story, or podium level, swimming pools set within the framework of a building, where the stainless pool shell will be tower craned into position and potentially requiring on-site welding if larger in size. (Shipping dictates whether welding is even necessary. Trucking sizes and site access control which format is used.)

Most projects begin with a set of drawings that include the familiar phrase: “Pool, by Others.” Occasionally, more detailed plans arrive from aquatic consultants, but in nearly every case, Natare must complete shop drawings and final engineering, and in that sense, every project is custom. This documentation process is the foundation of risk management and quality control.

Ideally, he says, the architect and aquatic consultant work through the design process to deliver a comprehensive set of plans. Each professional plays their role, and when it works, the result is something greater than the sum of its parts.

Albertson is clear about where he believes manufacturers fit: “We don’t want to play pool contractor. Our primary role is to be a manufacturer and fabricator, while helping with design as needed.”

That said, he also notes that Natare is not just a manufacturer in the traditional sense: “Anything we build — pools, bulkheads, gutter systems, filters — we’re comfortable installing ourselves, right down to welding on site.”

Growth and Flexibility

Although podium-level and rooftop pools remain a major driver of demand, stainless vessels are no longer limited to over-structure applications.

“What’s different about Natare is that we don’t just build for elevated conditions — we design stainless steel pool systems for on-grade and in-ground installations as well. And that’s where we’re seeing the most growth,” Albertson says.

He adds: “For each of the last five years, we’ve installed more in-ground stainless pools than we did in my first eight years here combined. That’s been fascinating to watch.”

One very important topic with over-story watershapes is dual containment. We have seen many projects that have had no intention of implementing a secondary containment vessel for stainless steel watershapes.

This is a road to catastrophic failure from our experience. Our work with forensic investigation and watershape failures has shown countlessly that most watershapes will have an issue in its lifespan, and that a backup to channel water away from habitable spaces, structures and expensive “real estate” within the facility below.

Regardless of location, part of the appeal lies in stainless steel’s inherent flexibility. “Concrete cracks when a building sways or the ground shifts — stainless doesn’t. That’s one reason it’s so well-suited for seismic areas and above-grade projects.”

And unlike concrete, an all-welded stainless vessel is watertight by design and due to the nature of the material itself. There’s a reason that ships are made of steel and not concrete.

“With stainless, you don’t need all the extra waterproofing layers and redundancies that concrete demands. An all-welded pool is watertight by design — and that’s still mind-boggling to some people.”

Material Integrity and Standards

Material choice and sourcing are critical. Natare uses only North American stainless steel, all within 300 miles of Indianapolis.

“Consistency and accountability matter too much to risk foreign supply,” Albertson says.

When it comes to grade, Natare’s standard is conservative. Type 304 stainless may be used outdoors in well-ventilated spaces, but Albertson strongly favors 316L stainless, particularly for indoor pools where condensation and chemical exposure create aggressive environments. Indoor steel vessels readily create condensation on the outside due to temperature differences. That moisture is slightly acidic and can attack substandard materials and welds.

Note: Welding rods must always match or exceed the vessel material grade.

Design Realities

Podium and rooftop projects demand tight design coordination. Deck heights, pedestal systems, ADA requirements, and site access all influence vessel dimensions. Coping and finish selections, handrail placement, and lift mounts are often the details that drive fabrication decisions.

Public health codes add another layer: many counties require interior finishes such as tile on stainless pools and spas, particularly on steps and benches where slip resistance is essential.

Documentation is the throughline. After design development, construction-level plans give way to fabrication shop drawings — the true “structural engineering” of the watershape.

Once fabrication begins, Albertson advises that watershapers stay in touch: periodic photo updates of welding and assembly can prevent costly misunderstandings. He also encourages watershapers to visit their facilities “to better understand the product and how its fabricated.”

Installation, Testing, and Delivery

As mentioned above, delivery logistics often determine how vessels are fabricated. Flatbeds can typically handle units up to about 15 by 40 feet; larger projects require on-site welding, hydrotesting, and passivation — all in less controlled environments.

Pools that are shipped in one piece undergo hydrotesting in the factory. The process identifies weak welds and accelerates corrosion in flawed materials, ensuring performance before delivery. With sectioned pools that require in filed welding, the testing is done in the field.

Not surprising, in our work, which has involved products from the spectrum of stainless manufacturers in projects of many different types, we’ve found that companies that are transparent about their quality control in the manufacturing process consistently deliver more reliable products. That is not the least bit surprising.

The Bigger Picture

One of stainless steel’s greatest appeals is durability. Unlike plaster — which, as Albertson points out is porous, chemically reactive, and dependent on so many variables. “This is why we use only either tile or PVC membranes, or a polished steel finish — stainless eliminates many vulnerabilities from the start.”

The overall result is longevity: “We recently upgraded our warranties to 25 years — not because the pools weren’t lasting, but because we realized we already had decades of proof. These systems last longer, and we know it.”

Finally, Albertson underscores the importance of early engagement:

“The earlier a watershaper can get us involved, the more money we can save a project. A few minutes in the beginning is worth a world of help.”

For watershapers, stainless vessels represent both opportunity and responsibility. They demand precision, planning, and collaboration — but when done right, they deliver watertight performance, architectural freedom, and a legacy of durability that concrete struggles to match.

Mark Holden is a licensed landscape architect and contractor, a university-level instructor, writer and forensic expert in the water industry for over thirty years.  His firm, Holdenwater in Fullerton, CA, addresses the design, engineering and forensics of water environments (holden@waterarchitecture.com).

Jeff Freeman has been a leader and innovator in the water-quality industry for over 30 years. In addition to lecturing and guiding agency regulatory policy, he has dedicated his career to advancing the technology of water purification and sanitization. He is Certified Pool Operator (CPO) and has U.S. military certification for water environments. (jfreeman@waterarchitecture.com).

Photos courtesy of Natare Pools.