Refinish a Pressure-Washer-Streaked Deck
Mauro Henrique has advice on the best way to refinish an old, discolored deck
My five-year-old mahogany deck was pressure-washed and now is streaked. What’s the best way to prepare the wood, and what finish do you recommend?
—Ron Cline, Palmyra, PA
Pressure-washing is not the best way to prep wood decks because of the damage it’s likely to cause. For routine maintenance, oxygen bleach applied with a hand-pump sprayer and scrubbed with a bristle brush is an effective and much gentler option. But if the existing finish has failed, it will have to be removed, and that requires a different approach.
I avoid using chemical strippers on decks because they’re messy, slow, and hard to clean up completely. With a tight-grained wood like mahogany, you’ll get better results by sanding off the old finish, as I did on the mahogany deck above. First, I smoothed the perimeter of the deck with a random-orbit sander, using 40-, 60-, and 80-grit sandpapers. Then I went over the deck’s field with an orbital floor sander, following the same grit sequence while always moving the sander in line with the decking. The nice thing about an orbital sander is that it uses a wide sanding pad, so you can’t gouge wood the way you can with a belt floor sander.
As for the finish on your mahogany, I recommend a penetrating oil-based stain, like Timeless Transparent Penetrating Wood Oil (Olympic). Not only does it let the wood’s beauty show through, it won’t peel or need to be sanded off again. Make sure the wood is dry and there’s no rain in the forecast, then apply a generous coat, using a brush along the edges and a lamb’s-wool pad in the field. Take care not to leave lap marks or puddles.
Next year, wash the deck as needed with a brush and oxygen-bleach cleaner. The wood should be ready for its next maintenance coat the following year, when it absorbs splashes of water in 10 minutes or less. High-traffic areas may need touching-up more frequently.
Shown: TOH painter Mauro Henrique removes the old finish from this mahogany deck using an orbital floor sander. Its gray tank in front is filled with sand to keep the paper firmly in contact with the wood.