A year ago, we had a crib dock installed at our cottage. Our installer suggested that we consider sealing the horizontal surface with a preservative. Is that a good idea? And how often should it be done?—Jeff Moore, West Nipissing, Ont.
Assuming that the dock is made of pressure-treated lumber (most crib docks are), “there’s no need to apply a wood preservative to the surface after installation,” says Jana Proctor of Timber Specialties in Campbellville, Ont. “The preservative that’s pressure-treated into the wood at the factory remains in the wood, and it doesn’t require redoing.” She thinks that the installer may have been suggesting that you apply some kind of sealer or waterproofing product to protect the surface of the dock from weathering. There are lots of products out there. “How often it would need to be reapplied would depend on the product, the dock’s exposure, and the wear on the dock,” she says.
But wait. You don’t need to put any product on the dock. Ever. You could allow it to weather. Plenty of people do, because they like that natural look or they want to avoid the guaranteed regular maintenance that is having to reapply a product for the entire life of the dock. Or both.
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“I’m not a fan of staining docks or decks,” says Marshall Black, the owner of Black Diamond Builders in Waubamik, Ont. “Inevitably, the stain becomes worn and ugly. Let it grey naturally. It’s beautiful and maintenance free.”
Proctor understands his point. “There’s really no product that you can just apply once,” she says. “They all break down. And a dock is in a harsh environment. It would put any product to the test.”
Plus, let’s be real: no matter how carefully you apply a product to the dock’s surface, it’s almost guaranteed that at least some of it would get into the lake, by, say, dripping between the boards. Okay, this isn’t an environmental disaster, but it’s also not good for the water.
Got a question for Cottage Q&A? Send it to answers@cottagelife.com.
This article was originally published in the Spring 2026 issue of Cottage Life.
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