If you’re building a wood pergola, consider staining and sealing the lumber before construction. Doing so allows you to work with the wood via ground level rather than staining it with the use of ladders. You can touch-up minor imperfections after construction.
Follow this tutorial for directions on how to stain and seal a pergola. We’ll show you how we tackled our modern two-tone design.
Staining and sealing a wood pergola, deck, or other outdoor structure doesn’t require two separate coats of stain and sealant. In fact, the opposite is true.
Stain is absorbed into the wood. Anything you put on top of it – even another coat of stain – won’t be able to absorb, so you’ll end up with a slimy or tacky surface.
One thorough but sparing coat of stain + sealer is the perfect protective covering.
Using only clear sealant provides water and weather-proofing but without UV protection. So the color of your clear-sealed wood will eventually change to a greyed-out version.
How to Stain Your Pergola
Lay your boards on some scrap 2x4s or an elevated surface. Be sure the ground can handle some drips. The surface underneath will likely get stain on it.
Use medium sandpaper (we used 180-grit) to lightly sand all sides of your pergola boards. Sanding opens up the wood pores, allowing the stain to penetrate deeply.
The rafters on this wood pergola will be a natural stain (Sikkens ProLuxe, available at our local paint store), and the frame of the pergola will be matte semi-transparent black.
Use a 4” brush and, keeping a wet edge, brush your stain onto the lumber. Apply in a single, thin but thorough coat along the grain, taking care to avoid brush marks.
Brush strokes will be visible after the stain absorbs into the wood and dries. The better you apply an even coat of stain, the better your end result will be. Brush away drips on the side of the boards before they dry.
Allow the stain to dry thoroughly, 24-72 hours, depending on your climate, temperature, and humidity.
Rotate the lumber and apply stain in the same way on all four sides, allowing thorough dry time between applications.
What Type of Stain is Best for a Pergola?
While there are many brands and types, Cabot is an excellent pergola wood stain available at most hardware stores.
You’ll need to choose between semi-solid and solid stains. Solid stains give an opaque look, resembling paint. Semi-solid, which is what this example uses, provides color but allows the wood grain to show through. It’s less saturated than a solid stain.
How to Stain a Pergola Frame
Use a natural brush proportionate to the lumber you’re staining. After stirring the stain, dip the bottom half of your bristles into the can.
Apply the stain onto your lumber in long, even strokes working in small sections. Don’t overbrush. The more you brush the stain, the more likely you are to see brush strokes after it dries.
Most lumber has an imperfection or two. To minimize the appearance of these imperfections, load the stain onto your brush and dab the bristle tips into the problem area.
After the lumber imperfection has been saturated, continue your long brush strokes down the board.
Before the stain starts to dry, stain the sides of the board and brush away drips. It’s important to do this while the stain is fresh. If the drips dry, they will be obvious (darker) and look odd on your pergola.
Repeat the staining process on the top and sides of all boards. Double-check for brush strokes and/or drips.
Don’t worry about the ends of your lumber at this point unless you have cut your wood to size.
The benefit of cutting your wood to size before installing the pergola is that you don’t waste any stain. The disadvantage is that you don’t have even 1/2″ of wiggle room in construction, should you need it. In this example, we will trim the boards during construction.
Allow the stain to dry for at least 24 hours. Don’t get it wet or dirty during that time, as this will have a major affect on the finish.
When the stain has dried, flip the boards over and repeat the process on the undersides. Remember to stain in long, even strokes, and check for drips down the sides again.
Final Tips for Sealing and Staining Your Pergola
With the stain fully absorbed and dry, you are ready to build your pergola. Of course, you can always apply stain after the pergola is built following these steps. But keep in mind that any transition from one stain to the next (for a two-tone pergola like this one) isn’t like paint. You must keep the stain neat and prevent it from overlapping on different colored boards.
While you might be ready to construct your redwood pergola, if you have the option, stain it first. When it’s built, you’ll be glad you did.