Green Team 16: Stainless Steel

With the pollen-rich landscapes of spring we discussed in our last post behind us and the sweltering days of summer beating down on our heads, the draw of cool shoreline breezes is tempting. What the casual beachgoer may not know, however, is that these waterfront locales often present challenging conditions that require special material applications to stand up to Mother Nature and ensure the longevity of coastal designs. Stainless steel plays a starring role in this success.

A popular medium in many design fields, stainless steel’s sleek finish and sharp lines appeal to both modern and contemporary sensibilities. Architects wrap buildings with it, industrial designers cloak gadgets in it, jewelry designers fashion accessories from it, and interior designers select it for kitchen sinks. Its corrosion-resistant properties also make it the best option for exterior applications in waterfront environments, compared to other metals (steel, galvanized steel, CORTEN steel, aluminum, iron, and bronze),— especially for brackish and saline waterways such as those of New York City’s coastal areas.

For our Hudson River Park Tribeca Section project, we designed a stainless steel railing at the pier’s edge, contributing to the installation’s longevity while enhancing the finish and aesthetic of this safety feature. Other cost-effective metals, like powder-coated or galvanized steel, were used for the park’s interior spaces. When designing with stainless steel, it is important that all attached metals, including connectors, fasteners, and anchors, are of the same material. Dissimilar metals in contact with stainless steel will accelerate corrosion and reduce the strength and lifespan of the product. This reaction is known as galvanic corrosion—a topic we’ll cover in a future post.

The railing at Pier 25 is constructed of Type 316 stainless steel to withstand the brackish Hudson River spray. 

Courtesy Elizabeth Felicella

Stainless steel is available in a multitude of grades, each classified based on the percentages of the various alloy components present in the product. Altering the alloy content affects the metal’s characteristics, including its strength, corrosion resistance, brittleness, magnetism, etc. For example, Type 304 is the most widely used grade of the metal in landscape applications, whereas Type 420 is utilized for cutlery. Type 316 stainless steel, which has greater nickel content than Type 304, offers enhanced corrosion resistance in saline environments and is therefore typically specified for marine and waterfront landscape installations. Type 316 is slightly more expensive compared to Type 304, due to its alloy content, but its durability makes it a valuable investment.  Type 316 stainless steel was used at our Hunts Point Landing project in the Bronx due to its proximity to Long Island Sound—a brackish waterway—whereas Type 304 was used at noteworthy non-marine projects including St. Louis’s Gateway Arch and New York City’s Unisphere.

Hunts Point Landing uses stainless steel in its pier railing, light posts, and overlook railing and mesh, due to its superior corrosion resistance and strength.

Courtesy Elizabeth Felicella

Beyond the corrosion resistance and notable strength of stainless steel, the breadth of available finishes and forms is another appealing aspect of this metal for designers. It is available in multiple finishes ranging from the highly polished look often used for interior applications or jewelry, to brushed finishes that more easily camouflage fingerprints and light debris, to a bead blast—almost matte—finish. Bead blast finish works well in exterior applications, as it retains far less heat than polished surfaces—no one wants to sit on a scalding hot bench as they catch a summer breeze off the water! At our Fulton Landing Pier, a number of forms and finishes were integrated into the project’s decorative railing, including polished or blasted stainless steel pipes, plates, cables and anchors, which enhanced its aesthetic appeal.

A detail of bead blasted posts, brushed plate, and stainless steel cable and anchors of the Fulton Landing Pier railing. 

Courtesy Mathews Nielsen Landscape Architects

Thanks to improved technology, stainless steel plate can be cut to almost any shape, freeing the designer from right angles, straight edges, or measured radii. Designers can provide their design drawings to fabricators who can then perfectly transform their 2D schematics into 3D forms via laser and water jet cutters. Our West Thames Park in Battery Park City incorporates stainless steel mesh and rods into a colorfully painted steel shade structure that provides dappled shade for now—until its twining vines are able to provide a dense canopy, woven throughout the overhead structure.

The shade structure with vines and stainless steel tables at West Thames Park in Tribeca.

Courtesy Elizabeth Felicella

Appropriate material selection is integral to the success and longevity of built environments. Also crucial to the success of a landscape, yet seldom discussed, is soil. Hidden out of sight below plants, mulch, and pavement, this vital material will be addressed in our next post.

Terrie Brightman, RLA, ASLA is a practicing landscape architect at Mathews Nielsen Landscape Architects in New York City with nine years of professional experience. Since receiving her BLA from the Pennsylvania State University, she has worked on riverfronts in Pittsburgh, private residences in California and Florida, a sustainable community in Turkey, and multiple public parks, plaza and waterfronts throughout New York City.