Why Wood Stains Are Important
To avoid performing frequent maintenance on your house’s exterior wood elements, you’ll need a long-lasting stain that holds up through weathering and regular wear and tear.
Wood stains are also a must for older decks. Before 2004 most decks were made of lumber pressure-treated with chromated copper arsenate (CCA) to fend off rot and insects. But concerns that arsenic, a toxin, could leach into the soil led to the introduction of other preservatives. If the wood in your deck is pressure-treated with CCA, the Environmental Protection Agency recommends regularly applying a penetrating coating, such as a semi-transparent or clear stain, to help reduce the leaching of arsenic.
If your deck is made of CCA lumber and its finish is flaking, we suggest calling a pro equipped to safely remove the old finish, dust, and debris.
But even on a new deck free from CCA, a good wood stain is crucial. Correctly applied, it can lend to the appearance of the wood while helping it last as long as possible.
How CR Tests Wood Stains
To evaluate exterior wood stains, CR’s test engineers apply two coats of stain to pine boards and place the boards on the roof of our headquarters in Yonkers, N.Y. We face them south and at an angle, like a roof, to intensify the effects of the sun and elements and to accelerate weathering. Because of our location in the Mid-Atlantic region, these boards are exposed to conditions typical of the Northeast’s four distinct seasons.
One year of testing tells you how a stain will look after one year on your deck, or about three years of weathering on your home’s vertical surfaces (siding or fences), as you’ll see in our wood stain ratings.
“The sun and water beat down on a deck, snow can pile up, and even dirt and mildew spores can settle on the flat surface,” says Rich Handel, the project leader who oversees CR’s tests of stains and paints. “All those issues are minimized on a vertical surface.”
The worst stains don’t hold up a year. The best remain close to new after three years, without fading, cracking, or mildew buildup. Some also fend off dirt. You’ll see these test results in the full view of our wood stain ratings by moving the Ratings & Specs slider bar to the right.
Need a little more help narrowing down your options? Check out CR’s list of the best and worst wood stains.
Wood Stains and the Environment
Today’s wood stains have to meet environmental rules that call for lower volatile organic compounds. VOCs are linked to pollution, smog, and respiratory problems, and can cause headaches and dizziness. Some may even be carcinogenic. Top stains from our tests meet these environmental standards and still look good after up to three years on a deck.
Types of Wood Stains
Finishes vary according to how much of the wood’s natural grain they show. The best opaque treatments tend to last the longest. But you may prefer a semi-transparent or clear finish for aesthetic reasons. Prices of the wood stains in our ratings range from $14 to $58 per gallon.
Solid Wood Stain
Also known as opaque, solid stains typically hold up the longest overall—the best should last three to five years on a deck. Solids hide the grain of the wood the way paint does, so they’re fine for pine decks, where seeing the grain isn’t important. They’re slightly less desirable on exotic hardwoods like ipe and tigerwood, where the natural appearance of the boards is part of the woods’ appeal.
Solid stains’ paintlike qualities have their drawbacks: They might build up a film, especially after several coats, which can peel, chip, and crack like paint. And performance varies widely—the stains in this category earn Overall Scores of 12 to 82 (out of a possible 100) in our tests.
Semi-Transparent Wood Stain
Semi-transparent stains color the wood but let the grain peek through, making them a good choice for wood that you want to show off—western red cedar, for instance.
In addition to typical semi-transparent stains, some brands may also offer what they label semi-solid and/or transparent stains or toners. They all work in a similar fashion by giving your wood more depth and protection without covering its natural grain.
But the best semi-transparent stain in our ratings isn’t as tough as the top solid stains, and our data suggest that this type of stain will probably last only two to three years on a deck. The stains in this category also vary widely in performance, garnering Overall Scores of 8 to 41. So compare the products in our ratings before you shop.
Clear Sealer
Clear sealers contain little or no pigment, along with water repellents. They’re ideal for accentuating the beauty of natural grain wood, although without anything to reflect ultraviolet rays, the wood will turn gray over time.
Going with this option also means you’ll probably have to restain your deck annually. As a group, the clear sealers we tested earn Overall Scores ranging from 4 to 27 (out of 100).
Wood Stain Brands
How to Prep a Deck for Staining
A newly built wood deck is ready to stain four to eight weeks after it’s installed. (This gives the wood, which is wet from the pressure-treating process, enough time to dry out.) Just clean the surface with soapy water and a scrub brush. Let it dry for about 24 hours, then apply the stain.
If you’re restaining a wood deck built before 2004, we recommend calling a professional to handle the cleanup and staining. Otherwise, you can take on the task yourself. Washing and sanding are typical first steps. If you’re using a pressure washer, read the machine’s manual before getting started and cover adjacent landscaping with plastic sheeting. The pressure needed is typically 1,500 pounds per square inch; a wide-angle spray tip of 25 to 40 degrees creates a relatively broad spray that protects the wood. Angle the spray and keep it between 6 and 12 inches away from wood surfaces. For more on pressure washing, read “Can This Surface Be Pressure-Washed?”
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