We replaced our old deck boards with new pressure-treated boards. It’s nice that they are a pleasant shade of light brown. How do I keep them close to the same colour? The contractor who built the deck said I should wait one year before doing anything. One year is up this fall. I don’t want the deck to turn grey. Should I put some type of sealer on it this summer? Will that keep the deck the same colour? Or, should I wait longer, and use a sienna brown stain? I recognize that I may have to do the sealer or stain every few years.—Gerry Bleau, via email
May have to? You probably will have to. Deciding to stain a deck is like deciding to adopt an African grey parrot: “Once you start, it is a lifelong commitment,” says Wayne Lennox, Cottage Life’s project builder. “I’m not a big fan of treating a deck with anything.” But it’s your deck. If brown is what you want, brown is what you shall have.
Lennox suggests avoiding a sealer. “They potentially seal moisture in as well as keep it out, possibly leading to mould. I would go with the stain.”
While you can slow weathering by using a semi-transparent stain, or a water repellent with added toner, “in general, you need colour in the product to protect the wood surface against UV damage and fading,” says Jana Proctor of Timber Specialties, a company that makes wood preservation and protection products. “If you like the original colour of the brown pressure-treated wood, choose a colour similar to it.” Try the product in a hard-to-notice test area first to make sure you like the look.
Great, you’re all set. But why did the contractor tell you to wait 12 months?
“More than 20 years ago, pressure-treated wood in Canada had a water repellent added to it at the factory level,” says Proctor. “You had to wait for that to wear off, usually for about a year, before you could apply something else,” she says. “But that hasn’t been done in so long, you’d think that information would have gone away by now.”
All our experts agreed that you’ve held off long enough. “You don’t need to wait a full calendar year,” says Marshall Black, a cottage, deck, and dock builder in McKellar, Ont. You do, however, need to make sure that the wood is completely dry. “You wouldn’t want to apply anything, say, after a night of rain.”
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The article was originally published in the August 2022 issue of Cottage Life.