Paint or stain for your deck: the plain answer

The short answer, with one exception

The Forest Products Laboratory's wood handbook says many fully exposed decks are more effectively finished with only a water-repellent preservative or a penetrating semi-transparent stain than with paint. Decks finished that way need refinishing more often than painted surfaces do, but refinishing is easy, because there's none of the laborious prep that peeled paint requires.

The exception is the porch. Exposed porch flooring is usually painted, the handbook says, with primers and paints formulated for porches because they resist abrasion and wear. A porch under a roof and a deck open to the sky are different jobs, even when the boards look alike.

How the two behave

The last two rows come from the handbook's table of expected service life, compiled for an average location in the continental U.S. The lifespans look similar. What differs is how each one fails, and what it takes to start over.

Why paint struggles on a deck

A deck is a floor that lives outdoors. A deck-finish study by researchers at Oregon State University and the Forest Products Laboratory describes what the surface faces: wetting from rain, dew and snow, ultraviolet light, and abrasion from foot traffic and furniture. Water pools on flat boards instead of running off.

A film has to hold up against all of that at once. The handbook explains why film-forming finishes struggle on horizontal surfaces: solid-color stains, which behave like paint, lack abrasion resistance and, because they form a film, tend to fail by flaking. Ordinary house paint has the same weakness, which is why porch floors get paint made to resist abrasion.

A penetrating stain has no film to flake. It simply thins out, first where people walk, and the boards underneath stay bare and ready for the next coat. New treated lumber adds its own wait, covered in staining pressure treated wood.

When paint is the right call

A covered porch floor

Porches get wet from windblown rain, so the handbook says to pretreat the wood with a water-repellent preservative before painting, then use primers and paints made for porches. Our look at porch paint ideas goes through colors and details.

A deck that's already painted

Purdue Extension says penetrating stain isn't effective over old paint, so a painted deck stays on the paint path unless you strip it back to bare wood. If you repaint, the surface still needs scraping, sanding and a good clean first.

A tired deck you want to hide

Sound but ugly boards, with gray patches and mismatched replacements, are where people reach for paint. A solid stain made for decks is the middle path, and our guide to solid and semi-transparent deck stain explains the trade-offs.

What the prep looks like for each

Stain prep is cleaning, brightening, drying and a light sanding, and our guide to preparing a deck for staining covers it step by step. The finish goes straight onto clean, dry, bare wood.

Paint has more layers to get right. The handbook's sequence for wood is a water-repellent preservative first, then at least three warm, sunny days for it to dry, then primer on the bare wood, then two coats of good paint. It says to apply enough primer to hide the grain and not to spread it thin. The handbook says a primer coat of the right thickness helps prevent premature paint failure, so skipping steps tends to backfire.

That's also the argument for stain on a typical deck: fewer layers means fewer places for the finish to let go.

Color and look

Stain keeps the wood in the picture. Purdue Extension says semi-transparent stains are especially popular in brown tones for a natural or rustic look, and they aren't available in white. Each board shows its own grain and color through the stain.

Paint can be any color and hides everything underneath, which is the point if the boards are blotchy or a mix of old and new. A chip or a worn spot shows the bare wood underneath. For a look at deep wood tones on cedar, see our cedar pergola stained dark brown.

What upkeep looks like

Stain asks for attention more often and for less effort each time. You walk the deck once a year, and when it starts to gray or the water soaks in, you clean it and add a coat. Purdue Extension says refinishing a semi-transparent stain takes no heavy scraping or sanding, just a stiff bristle brush and a new coat. Our guide to how long deck stain lasts has the ranges.

Paint asks for attention less often and for much more effort when it comes. A deck that starts to peel needs the failing paint scraped and sanded off, any bare spots primed and the whole surface repainted. Peeling can spread, since lifted edges give water a way in underneath.

A quick way to decide

Choose stain if:

• The deck is fully exposed to sun and rain.
• The boards are sound and you like seeing the grain.
• You'd rather clean and recoat than scrape and repaint.
• The deck is bare or has only a semi-transparent stain on it now.

Choose paint, or a solid finish made for decks, if:

• The deck is already painted and you don't want to strip it.
• It's a covered porch floor and you want a specific color.
• The boards are sound but badly mismatched, and you want an even look.
• You're prepared for the scraping and sanding that come when it fails.

Getting it done right

Whatever you choose, prep decides how long it lasts. If you'd like us to stain or refinish your deck, ask for a free estimate and tell us what's on it now. George visits if he needs to see it, then sends a written quote and a start date.

One last note: everything here is about wood decks. Composite decking has its own care rules from its maker, so read those before putting any finish on it, and say which kind you have when you call.