When building a dock, there are many factors to take into consideration: cost, safety, durability, and longevity. In this article we’ll discuss some differences between pressure treated pine, exotic hardwoods, and composite to help you find the best material for your dock.
The only real advantage to using pressure-treated pine on a dock is cost. It’s by far the least expensive option, but as is often the case, you get what you pay for. With proper care and refinishing every two to three years, the dock might last 10-15 years. Splintering, warping, cracking, and rotting is common with pressure-treated Pine, making it unsafe and likely to cause injury, especially on bare feet or with children.
Exotic hardwoods cost more than pressure-treated pine, but that cost is recouped on the dock’s life expectancy. A dock crafted from Ipe, Cumaru, Garapa, or Tigerwood, if properly cared for, can last 25-30 years before structural maintenance is required. Not only will a dock made of these wood species last longer than pressure-treated Pine, but it will also stay smooth with a much lower chance of splintering, rotting, and warping. If insurance is a consideration, Ipe is a good choice, as it can receive up to a Class A fire rating.
To keep an exotic hardwood looking exactly as it did when it was installed, an UV-blocking oil must be applied every year, or you can choose to allow the wood to age naturally to a silvery-gray patina. This is a purely aesthetic decision, and the quality of the wood will not degrade if it’s allowed to weather naturally.
A composite material, made from recycled plastic and wood fiber, is also a good option for a dock. It’s pricier than pressure-treated Pine, but is almost maintenance free, won’t splinter, and doesn’t ever need to be refinished. It can, however, take on mildew stains, especially if it’s not swept and washed regularly. Because it’s so heavy, a composite dock will need more joist support than with wood or it will sag. Composite decking also heats up in the sun and can feel uncomfortably hot on bare feet.
While exotic hardwoods and composite decking have clear advantages over pressure-treated Pine, choosing between those two choices simply comes down to personal preference and budget. Choose an exotic hardwood like Ipe, Cumaru, Garapa, Tigerwood, or composite decking for your dock and it will have a long life expectancy, remain safe, and look beautiful for decades.