Strucutral plastic lumber marine fendering

Marine-Grade Plastic Lumber

Be it from boats, barges, or Mother Nature herself, marine infrastructure applications are bound to take a beating. Finding a sturdy, durable material to withstand it all can be quite a challenge. That’s where Tangent comes in. Our structurally engineered marine-grade plastic lumber and composite marine decking materials are a great alternative to traditional wood, metal or concrete holding up in even the harshest environments.

Marine Applications

Bridge Fenders

Bridge Fenders

Safeguard Your Bridges with Structural Recycled Plastic Lumber
Fenders are bumpers constructed around docks, piers and bridges providing support and protection against accidental damage. As boats, vessels and barges travel along the water, fender systems help absorb energy from impact. Fendering systems perform only as well as the building material that they are constructed from. Traditional building materials like wood, metal and concrete can break down, rot, mold and decay over time due to submersion in water. Constructed in and around water, and chemicals like calcium and potassium found in seawater can deteriorate traditional building materials, causing the need for future repairs and replacement. Not to mention, when large vessels bump up against wood, the friction that is created can cause the fendering system to splinter.

Tangent has over 25 years of proven experience in manufacturing marine-grade structural HDPE plastic lumber decking pier protection systems. Our Marine Piles and Timbers are the ideal material for bridge rendering systems due to their high energy absorption through recoverable deflection, as well as resistance to moisture and corrosive substances, like salt water.

marine fender system


Protect Your Marine Projects the Right Way with Structural Plastic Lumber

Wharves receive heavy traffic, and in some cases, heavy cargo loads. Traditional building materials like wood, metal and concrete can require constant maintenance and repairs. Wood can rot and mold due to consistent exposure to moisture; concrete can break down due to compounds found in seawater, like calcium and potassium; metal can rust and corrode. This destroys the material, ultimately resulting in cracks, splinters and breaks. Using a structural and long-lasting building materials like Tangent’s plastic marine decking can save you maintenance costs and keep your docks, piers, and wharves intact for generations to come.

Wharf Fender


Cluster Together with a Durable Building Material Built to Last
Dolphins are marine structures that provide pier protection from vessels and barges and serve as a mooring point and hold navigational aids, safety information and in some cases, advertising. They are typically constructed using multiple piles and are installed offshore.

Dolphins are located partially underwater and require a building material that is structurally sturdy, low-maintenance and easy to install. Traditional building materials like wood, metal and concrete break down over time, causing the need for repairs and replacement. Chemicals found in seawater, like calcium and potassium, can eat away at wood timbers and concrete, causing them to splinter or crack, and metal can corrode and rust when exposed to consistent moisture. Not only does the material break down over time, but it also leeches chemicals into the water that can harm sea life and deteriorate drinking water safety.

Tangent’s Structural marine-grade plastic lumber materials are the perfect solution. Long-lasting and durable, Tangent structural solutions are low-maintenance and do not rot, corrode or disintegrate and are resistant to corrosive chemicals and marine borers.

marine dolphin

Marine Piles

Marine Piles are used in bridge pier protection (bridge fenders), pier & wharf fenders, lock gates and guide-walls are subject to the harshest conditions. Traditionally built with timber, today’s facility owners largely specify composite marine decking due to its low-maintenance and long-lasting durability. Tangent Marine Piles are our advanced structural recycled plastic lumber decking solution that has been carefully engineered with pultruded rebar supplemented with reinforcing structural fibers throughout the cross-section. Tangent’s Marine Piles absorb the energy of vessel impact through recoverable deflection and are also a superior solution due to resistance to moisture, including salt water. Long-lasting and extremely durable, our Marine Piles increase your ROI and lower your maintenance costs.

Tangent Marine Piles are produced with high quality, recycled plastic resin along with our proprietary blend of fiberglass filaments, UV inhibitors and other additives to assure our customers year over year performance.


· Sizes up to 16″ cross-sections
· No wood / organic fibers to degrade – no metal / materials to corrode resulting in constant performance in harsh environments.
· ASTM test data to back up performance specifications
· Complete, in-house tooling & manufacturing to allow for custom design shapes and performance requirements.

Why Is Plastic a Greener Option for Marine Piling?
Nav Aids

Navigational Aids & Channel Markers

Safely Guide Vessels with a Long-Term Solution
Navigational aids provide helpful information for boaters and operators. Typically referred to as the “waterway road signs”, these structures hold important information like location, distance to a specific destination, traffic speeds, safety information and advertisements. The use of navigational aids is extremely important for boat operators and help maintain safety on the water. It’s important for these waterway road signs to be constructed from high-quality material that can withstand extreme moisture and boat and vessel impact. Traditional building materials like wood and metal can mold, corrode and break down due to water submersion. Like road signs, these must be maintained at all times.

Tangent’s Structural Materials are the high-quality solution that lasts for generations to come. Resistant to moisture, salt water, marine borers and crustaceans, our Structural composite marine decking material is the ideal, low-maintenance solution for navigation aids and channel markers.

marine dolphin
Docks & Piers

Docks & Piers

Extend the Life of Your Dock with Structural HDPE Plastic Marine Decking Materials

Docks are boardwalks or walkways that are constructed over a body of water, usually a lake, river or ocean. These structures must be durable and long-lasting as they play an important part in marine transportation and help keep the process smooth-sailing. Saltwater and other chemicals in seawater can break down traditional building materials like wood, metal, and concrete. When constructing docks and wharves, considering the foundation, soil and the potential for moving water or currents is important. Wood can rot and mold due to consistent exposure to moisture, concrete can break down due to compounds found in seawater, like calcium and potassium, and metal can rust and corrode. This breaks down the material, ultimately resulting in cracks, splinters, and breaks.

Instead, choose the long-term, low-maintenance solution with Tangent Structural Materials. Using our plastic lumber decking materials can save you maintenance costs and keep your docks and piers looking beautiful for generations to come.

Strucutral plastic lumber marine fendering
Marine Decking

Marine Decking

Tangent’s composite marine decking is the durable, low-maintenance marine dock board that excels with wood-like aesthetics. Tangent’s marine-grade plastic lumber is highly resilient and engineered for residential boat docks, marinas, piers, and light commercial applications. It is the ideal decking investment for waterfront properties and structures.

Tangent’s plastic lumber decking is made using a blend of recycled plastic, like milk containers, with other strengthening agents and additives to form a proprietary material. Certified by third-party GreenCircle™, the green building standards are recognized by the National Green Building Standard and LEED and meet the Federal Trade Commission Green Guidelines.

Product Features:

  • Requires no waterproofing, staining, or painting
  • Quick install- No pre-drilling needed for fasteners. Work with TanDeck using traditional work tools.
  • Wood-Free- Exceptional resistance to moisture, fading, insects, splintering, warping and exposure to the harsh marine environment.
  • Strong and practical- 5/4×6 TanDeck allows up to 16″ on-center spans and 2×6 up to 24″ to replace wood decking for residential and light commercial applications. TanDeck is embossed with a wood-like texture on both faces.
  • Wood grain embossed finish on surface for aesthetics and slip-resistance.
  • Simple to clean with mild soap and rinsing with water
  • 50-year limited product waranty.
  • Profiles- Deck Boards: 1″ x 6”, 2” x 6”.


Secure Your Project with a Structural Plastic Lumber Substructure
Substructure joists are installed between beams to help transfer load-bearing weight to other members and to support the top boards. Stringers are beams that run lengthwise and also help transfer weight for more even distribution and are typically installed on top of the joists. Oftentimes, structural support beams like joists and stringers are exposed to high moisture. Bridges and docks are built over and in water and due to changing tides, sometimes these beams can be completely submerged. Traditional building materials like wood and metal provide structural integrity but can fall short in a wet environment. Constant exposure to moisture can rot and break down traditional wood, and metal will rust and corrode, which can leach harmful chemicals into the water, endangering the environment and sea life. Chemically-treated wood also will leach chemicals, so it’s best to use a material that isn’t treated at all.

Tangent’s structural plastic marine decking materials not only offer an extremely strong and durable solution, but are also long-lasting and low-maintenance. With a warrantable life of 50 years, choose a substructure that will support your project for the long-haul.

long-lasting substructure Assabet River Rail Trail case study

With Tangent’s wide variety of sizes, colors and product lines, you’re sure to find the right material for your job.