TL;DR:
Choosing dock decking comes down to budget, maintenance, and aesthetics.
- Treated lumber is affordable and easy to work with but needs regular upkeep.
- Marine-grade plastic decking (like Sunwalk) is ultra-durable, slip-resistant, and maintenance-free — perfect for tough environments.
- Composite decking (like Trex or TimberTech) blends wood and plastic for a natural look with long-lasting performance.
Your ideal decking depends on whether you value cost, convenience, or overall look most.
When you’re building or upgrading a dock, your decking choice makes all the difference. It’s what you’ll feel underfoot, what your guests will see first, and what determines how much maintenance you’ll face down the road.
There’s no one-size-fits-all answer — but there are three materials that rise above the rest: treated lumber, marine-grade plastic decking, and composite decking. Each has its strengths, trade-offs, and best-use cases. Here’s how to decide which one fits your dock (and your lifestyle).
1. Pressure-Treated Lumber — The Classic Go-To
If you’ve been around docks for a while, you know treated lumber is the old reliable. It’s been the standard for decades — affordable, strong, and easy to work with.
Treated lumber is wood infused with preservatives to resist rot and insects, making it a solid option for freshwater docks. It’s simple to cut, fasten, and repair, and it gives your dock that timeless, natural wood look.
Pros:
- Budget-friendly and widely available
- Easy to customize and repair
- Classic wood appearance
Cons:
- Requires sealing or staining to extend lifespan
- Can splinter or warp if not maintained
- Heavier than plastic or composite boards
Best for: DIY builders and budget-conscious homeowners who don’t mind routine maintenance.
2. Marine-Grade Plastic Decking — Lightweight, Strong, and Zero Maintenance
Plastic decking has become the go-to for anyone wanting a long-lasting, low-maintenance dock. Unlike wood, marine-grade plastic decking is completely impervious to rot, moisture, and UV damage — making it perfect for harsh waterfront environments.
One of the most popular options in this category is Sunwalk Decking, made from reinforced polypropylene. It’s ultra-strong yet lightweight, slip-resistant, and stays cooler under the sun than many solid-surface boards. Plus, its open-grid design allows water to drain freely, which helps prevent standing water and algae growth.
Other brands use solid marine-grade PVC or HDPE (high-density polyethylene) to achieve similar benefits — offering smooth finishes, color options, and long-term durability.
Pros:
- 100% waterproof — won’t rot, mold, or mildew
- Maintenance-free and UV-resistant
- Lightweight, slip-resistant, and cool underfoot
Cons:
- More expensive upfront than treated lumber
- Industrial appearance (depending on brand/style)
Best for: Homeowners who want an ultra-durable, maintenance-free dock that looks clean and performs flawlessly year after year.
3. Composite Decking — The Best of Both Worlds
Composite decking blends wood fibers and recycled plastics, giving you the look of real wood with much less maintenance. Brands like Trex and TimberTech have perfected this formula to create boards that are dense, durable, and fade-resistant.
Composites are heavier than pure plastic decking but feel more traditional underfoot — and visually, they’re hard to beat. Many options mimic the texture and color of natural wood so closely that most people won’t notice the difference.
Pros:
- Low maintenance — no sealing, staining, or painting
- Won’t splinter, rot, or warp
- Long lifespan with solid manufacturer warranties
Cons:
- Higher upfront cost than treated lumber
- Can retain more heat on hot days
- Far heavier than plastic, and often even heavier than lumber decking
Best for: Homeowners who want a dock that looks high-end and natural without the constant maintenance of real wood.
Final Thoughts
Each decking option has its place:
- Treated lumber: Best for DIY’ers who want affordability and a natural look.
- Marine-grade plastic decking: Perfect for anyone who wants strength, light weight, and zero maintenance.
- Composite decking: The ideal middle ground between wood’s beauty and plastic’s longevity.
Whichever you choose, make sure your dock’s foundation is built to match — with durable floats and hardware that can handle the elements. Explore our selection of dock floats, hardware, and DIY kits at The Dock Shop, or contact us to plan the perfect dock for your waterfront.