Like a good football defense, stain is all about penetration. Whereas paint adheres to a surface, stains penetrate and protect the substrate material—which can be an advantage, particularly in exterior surfaces such as wood siding, shingles, outdoor structures, and furniture that are subjected to harsh conditions.

Tim Carter, best known as a syndicated columnist and the founder of AskTheBuilder.com, gives advice on all aspects of building and remodeling, but painting is close to his heart: His first business venture was a summer house-painting gig he did with a friend. When making the choice between an oil-based, oil-latex, or water-based stain, Carter says,

“The first thing a painter needs to do is stop and look at the specification sheet of the product. The manufacturer will almost always provide a great description of the best use or uses of the product. If you’re in doubt, you need to stop and contact the manufacturer to match up the proper product to the task at hand. Never ‘hope’ a coating product will work. Hope is for amateurs.”

In general, water-based stains are your best bet for surfaces that have been previously painted or stained with oil-based stain, as well as woods that have a natural resistance to rotting, such as cedar, redwood and cypress. They offer benefits such as better color retention, quicker drying time, and soap and water cleanup, as well as mildew resistance, less odor and being nonflammable.

Oil-based stains, which offer better penetration and durability, are suited for decks and other areas exposed to sun, wind, rain, snow, and temperature changes. The longer drying time requires planning, but also gives you more time to achieve an even finish. The downside comes in cleanup and a need for attention to ventilation (because they contain more VOCs), as well as proper disposal, in order to prevent fire and pollution. You’ll also want to make sure you invest in an oil-based stain that is mildew resistant.

Finally, the newer hybrid oil-latex stains offer some of the benefits of both oil- and water-based stains, and can be used for fences, siding, planters and wood patio furniture—but they’re not intended for horizontal surfaces subject to foot traffic.

CONSIDERING COLOR AND OPACITY

Today’s stains are available in a variety of natural wood tones as well as blues, greens, reds and yellows. But you’ll want to advise property owners about the long-term changes that can occur in certain color choices—particularly with direct UV rays that pound horizontal surfaces when the sun is high in the sky. “Any painter who’s been painting for decades will tell you that certain colors don’t fare well in harsh sunlight,” Carter says. “Some deeper reds and blues can have fading issues, although technology and great ingredients are making colors last longer with less fade.”

Your next consultative aspect will be opacity. The opacity defines the amount of visible wood grain that can be seen, but also affects what surfaces it can be applied to, the amount of protection offered to the substrate, and the life expectancy of the coating. Semitransparent stains allow the most grain pattern to show through and can be applied over bare wood or previously semitransparent stained wood that hasn’t been sealed; the low opacity also means less pigment and shorter lifespan. Semisolid stains are the next step up, almost completely hiding the natural wood grain and color while offering a more durable finish than semitransparent stains. Solid (also known as opaque) stains, which are the most durable of all, hide the grain entirely and, in many cases, can be applied over previously painted surfaces.

THINKING ABOUT PREP

Even the most expensive, highest-quality stains won’t last if you haven’t prepared the surface properly. “Realize that the chemistry of almost all coatings produces a colored glue,” Carter says. “If you want great adhesion, you need to remove dirt, oil, grease and dust. Increasing the surface area available for adhesion can help, which is what sanding does on a microscopic level.”

For surfaces that have been painted or sealed previously, those coatings need to be removed with a chemical stripper or by sanding. (As mentioned a moment ago, solid stains provide the most latitude in application over a prior coat.) Before applying the new stain, the surface should be clean, dry, and free of mildew, dust, and loose wood fibers.

Ideally, bare wood that is gray or weathered should be sanded down for optimum adhesion. On the other end of the spectrum, new wood also requires a strategic approach and consideration of which type of stain to use. “Green lumber can be liberating lots of stored-up water,” Carter says. “If you apply a stain that forms a film, it’s possible the vapor pressure can cause the stain to peel or crack.”

Again, Carter’s recommendation is to read the product label and contact the stain manufacturer if you have any doubts. “This due diligence can save you from a callback, or a bad online review that doesn’t go away,” he says.

HOW LONG WILL A STAIN JOB LAST?

It’s easy to dread the ever-looming customer question, “How long before I have to stain this again?” Carter believes the truthful answer is: It depends. “It depends on the weather, on how well the property owner cleans the surface, and on what the property owner uses to clean the surface on a regular basis,” he says.

For example, if it’s vertical siding that’s been stained, a home owner who washes the house each year with liquid soap and water, just as they might wash their car, could get an extra 50% or more from the service life of the stain job. “The home owner who washes their house, removing all the food for mildew, mold and algae could have their house looking great for five or seven years before it needs attention,” Carter says.

What happens if they don’t? “A customer that doesn’t wash off dust, dirt, aerosol sap from trees, or other substances, might have a stain job that’s looking shabby in just a few years,” Carter says.

While that might mean additional staining work for you as a painting contractor, the hazard is that you might get blamed for poor workmanship. Better to do the job right, have a happy property owner, and watch the referrals flow in.

---

SPRAY, ROLL OR BRUSH?

What’s the best method for applying stain? “This is a loaded question, much like you load paint onto a brush!” says Carter. “You can’t always do what might be the best method of application in all situations. While you might like to spray wood cabinets in a kitchen remodel, it’s possible the process could be harmful to surrounding surfaces, animals, plants or people.” Since each application method produces a different texture, your best approach will be to consult with the customer—because they may value the finish texture as much as the color and the sheen. Just make sure to take into account the application time and drying time when you’re creating an estimate!

---

MORE TIPS FROM TIM

Tim carter offers a free weekly newsletter to get valuable tips that can help you grow your painting business. subscribe at askthebuilder.com