Solid or semi-transparent deck stain: how each one wears

The two stains side by side

The rest of this guide explains each row, starting with how the two finishes behave once they're on the wood.

How semi-transparent stain works

Semi-transparent stain is thin and carries pigment. Oil-based versions soak into the wood rather than sitting on it, and the pigment gives color and some protection from sunlight while the grain stays visible. Waterborne versions don't penetrate as well and form a thin film, though they're easier to apply and less likely to show lap marks.

How much stain a deck takes depends on the boards. The Forest Products Laboratory's handbook gives coverage of about 200 to 400 square feet per gallon on smooth wood and 100 to 200 on rough or weathered wood. Weathered boards drink roughly twice as much, which is also why stain tends to perform better on them.

Pigment matters for how long it lasts. In a deck-finish test by researchers at Oregon State University and the Forest Products Laboratory, clear or lightly tinted finishes lasted only one to two years on decks. The authors note that adding pigment to reach a semi-transparent stain can stretch that to four to five years, at the cost of hiding more of the wood's natural character.

How solid stain works

Solid stain behaves like paint. It covers the grain, hides color differences between boards, and forms a continuous film. The handbook says solid-color stains "act much like paint," and that on vertical surfaces, two coats over a good primer should last about as long as a good paint system.

A deck is the hardest place to ask a film to work. The handbook says solid-color stains shouldn't be used on any horizontal surface unless they're specially formulated for decks, because they lack abrasion resistance and, since they form a film, tend to fail by flaking. Its expected-life table rates solid-color stain as a low-suitability choice for decking, at one to two years.

That table dates from 1999, and the handbook leaves room for products made for decks. Still, the logic holds: a film on a surface people walk on, with water pooling on it, is under more stress than a film on a wall.

Choosing by the shape your deck is in

New or lightly weathered boards

Semi-transparent stain is the usual answer. It shows off clean wood, and when it wears, you clean the deck and add a coat instead of stripping a film.

Gray, worn or patchy boards

Weathered, rough boards are where semi-transparent stain does well. The handbook rates it as highly suitable on weathered decking, with three to six years expected, against one to two for solid-color stain. If the deck has replaced boards that stand out, though, a solid finish will even them out where a semi-transparent stain won't, because the wood shows through.

A deck that already has solid stain or paint

Purdue Extension's finishing guide says semi-transparent stain isn't effective over a solid-color stain or old paint. So you have two choices: stay with a solid finish made for decks, or strip back to bare wood first. Our guide on whether to paint or stain a deck covers the paint side of that choice. On a brand-new deck, also read how long to wait before staining treated wood.

What happens when each one wears out

A semi-transparent stain fades. The color thins, the boards start to gray, and the worn paths show first. Purdue Extension describes refinishing as easy: no heavy scraping or sanding, just a stiff bristle brush to remove surface dirt, dust and loose wood fibers, then a new coat. The second coat often lasts longer because it soaks into the small surface cracks that open up as wood weathers.

A solid stain fails the way paint does, by flaking and peeling. The handbook says that when cracking and peeling are extensive, it's usually best to remove all the finish from the affected area, and that stripping is slow, often difficult work. That's the trade-off of choosing a film: it hides more at the start and is harder to end. For durability numbers on both, see our guide to how long deck stain lasts.

Color and look

Semi-transparent stains come mostly in wood tones. Purdue Extension notes they're popular in brown tones for the natural or rustic look and aren't available in white. Because the wood shows through, the same stain looks a little different on each board, which is part of the appeal.

Solid stain can be nearly any color, which is its real advantage if you want the deck to match the trim or read as painted. For a sense of how a deep wood tone looks on cedar, see our cedar pergola stained dark brown. If you're torn between wood tones, our guide to the best stain for a cedar deck goes further.

Application matters more than the label

A good stain applied badly still fails. The handbook is specific about this: limit semi-transparent stain to what the wood can absorb, because roller and spray application can put too much on a deck's horizontal surfaces. On smooth boards, a brush is the best method. Stain that doesn't soak in can dry into a shiny film on top, so the handbook says to wipe off the excess about an hour after the second coat. Each type also dries on its own schedule, laid out in our post on stain drying times.

It also says not to mix brands or batches, since color can shift, and to stir often so pigment doesn't settle.

Neither one fixes poor prep

Whichever stain you choose, it can only be as good as the surface under it. Dirt, mildew and old finish all get in the way, and the Forest Products Laboratory notes that mildew growth is the main cause of discoloration on both painted and unpainted wood.

That's why the cleaning and drying steps matter more than the product on the shelf. Our guide to preparing a deck for staining walks through them in order, and our guide to the best time to stain a deck covers the weather that goes with them.

Choosing for your own deck

If your boards are sound, start with semi-transparent stain. If they're worn, mismatched or already coated, the answer depends on what's on the deck now and how much stripping you're willing to take on. For a deck we're asked to stain or refinish, George visits if he needs to see it, then sends a written quote and a start date.

When you're ready, ask for a free estimate and tell us what's on the deck now.