Pros' guide to deck refinishing

By Bill and Kevin Burnett
Inman News®

Q: It's time to refinish my sun-pounded deck, and I was wondering whether you'd recommend sanding it down again. I did so about three years ago, and although I love the freshly finished look, I'm not sure how many times I should sand the wood.

So I'm hoping that I can just seal it well and be done with it. The last time, I used a Cabot product called Pacific Coast Redwood-Clear. I liked it, but it's worn down now.

A: Pick a nice couple of days -- not too hot or too cold -- and get the refinishing part out of the way.

You did well to get three years out of the Cabot product. We usually suggest a product we've had good luck with: Superdeck by DuckBack. But since the Cabot product works for you and you like the look, stick with it.

We understand the concern about continuing to sand the deck. But the little bit of wood fiber removed with a sander won't affect the structural integrity of the decking. A 1 1/2-inch deck board can take a dozen or more sandings with no problem.

That being said, sanding is a lot of work. You can get the same clean, fresh surface with a good pressure washing. A pressure washer removes the deteriorated finish and some of the decayed wood fiber leaving a like-new surface after the wood dries. This machine attaches to a garden hose and sends out a pressurized stream of water that makes short work of old finishes, surface dirt, mold and mildew.

To look its best and prolong its life, a deck should be cleaned and treated with a preservative every one to two years depending on exposure to weather and use. A maintenance program consisting of cleaning the deck, removing any mildew and applying a new coat of preservative is the ticket.

We recommend using a pressure washer that can produce a stream of water of at least 1,500 pounds per square inch (psi). A word of caution here. Nozzles are adjustable from a stream the size of a pencil to a broad fan. For deck cleaning use the fan setting and be sure to keep the wand moving so you don't blast softer wood away from the surface and leave a rippled effect on the deck.

If your deck is really showing its age, consider using a chemical deck cleaner. Cleaners are available where pressure washers are rented or sold. We've had good luck with a product called Restore-X.

Pressure washers can be multitaskers, useful for washing the car or blasting moss off a shady sidewalk. So purchasing as opposed to renting might make some sense. If you have good neighbors, consider making a communal purchase and sharing.

Once cleaning is complete, thoroughly rinse the deck with clear water if you used a chemical cleaner, and allow the deck to dry for several days. Lightly hand sand the decking to provide some tooth for the preservative to penetrate. Apply the Cabot product you like according to package instructions. If a second coat is allowed, do a quick sanding between coats.

It's a fair amount of work, but we're confident you'll get another three years out of this job.