Paint or Stain: Which Is Right For Your Deck?
Stain your deck the wood's natural beauty shows through, but you might have to redo the job soon. Paint it and the wood will be protected, but you'll lose the look of the wood grain. So which should you choose?
Unfortunately, there's no simple this-or-that answer. Paint the railing and you won't have to refinish it any time soon, but you'll hide the wood's colour, grain pattern, and texture. Stain it and you'll accentuate all these characteristics, but you'll be stripping it back and starting again sooner than if you'd used paint.
Either way, finishing the railing is critical, because unprotected wood left to the elements gets ugly fast. Moisture is absorbed by wood, causing it to twist, warp, and crack as it swells and shrinks. Ultraviolet radiation from the sun discolours wood and breaks down its lignin, the natural glue that holds the fibres together. This invites more moisture and, worse, wood-decay fungi, which secrete enzymes that rot wood fibres. Even cedar, which contains weather-resistant oils, can look pretty rough after a few seasons.
Painting your railing will give it the best possible, longest lasting protection against the elements. High-quality, water-based latex paints are more flexible than oil-based paints and can withstand the wood's moisture fluctuations better. The high solids content in paints helps form a thick, opaque film on the surface that hides imperfections, resists moisture, and blocks UV rays. If done right, a painted surface could last 10 years before you'd need to strip it back and refinish.
However, painting is a messy job, and you'll need to prepare, preserve, and prime the wood first (see "Finish Exterior Wood Like a Pro," above). Plus, you've got to be handy with a paintbrush if you want the project to look good. It's worth noting that paints and other film-forming finishes aren't ideal for large horizontal surfaces that get a lot of wear, such as decks. Instead, use a water-repellent stain or other penetrating finish.
If you stain your railing, don't expect the same longevity you get with paint. Stains soak deep into the wood, filling in microscopic gaps that would otherwise absorb moisture. This helps keep the wood stable, but it's not as effective as a paint's protective coating. On the upside, most stains are formulated with a wood preservative, so mould and rot shouldn't be a problem. However, stains don't do a good job blocking UV, and that could be a major factor if your railing gets a lot of sun. "Transparent and semi-transparent stains contain some pigment and offer a bit of UV resistance, but the clearer the stain, the less protection you'll get.
The wood will grey after a few yearsA solid-colour stain might offer a compromise.
"Whereas all paints are UV-resistant, only solid-colour stains offer comparable protection. These near-opaque stains form a protective film on the surface similar to paint, but they're thinner so they won't hide the wood's texture. Plus, you can buy them in different shades, so matching your cedar's natural colour shouldn't be a problem. A solid-colour stain might last eight years or more.
One last consideration: Many homeowners find stains easier to apply than paint, so even though you'll refinish the railing more often, it'll be a lot less work each time. "
Finish Exterior Wood Like a Pro
1 Clean surfaces thoroughly before painting. Stripping existing finishes and removing dirt, dust, mildew, and loose wood fibres improves adhesion.
2 Set nails and screws below the surface, and fill the holes with an exterior-grade wood filler to help keep moisture out.
3 Apply a paintable water-repellent preservative before priming to inhibit mildew and rot. If staining, use a product that already contains a preservative.
4 Priming all surfaces before painting improves adhesion and moisture protection, adding as much as two years to the life of the finish.
5 Reduce moisture absorption by painting all surfaces, including those not directly exposed to the elements. Coating end grain is especially important.
6 Repeat as necessary. In fact, two coats of stain or paint protects wood for up to twice as long as a single coat.