Spec notes · 2026-09-03

Concrete staining vs. coating for a patio: pick by what the slab has to survive

A stain and a coating fix the same ugly patio and have almost nothing else in common. A stain soaks into the concrete and changes its color. A coating sits on top of the concrete and gives it a new surface. One becomes part of the slab, the other protects it. Which one you want depends less on the look you’re after than on what the patio has to live through, and around Cape Girardeau that’s a short, specific list.

What concrete staining does to a slab

Acid stains react with the lime in the concrete and leave mineral color behind, mottled and uneven in the way people mean when they say a patio looks like stone. Water-based stains and dyes are more like a wash of color that soaks into the pores. Either way, the stain adds nothing you can feel. The surface stays exactly as smooth or rough as it was, and every trowel mark, patch, and old repair shows through, sometimes more clearly than before. Stain is honest about the slab underneath it.

Because there’s no film, there’s nothing to peel. That’s the whole appeal outside. The part that ages is the sealer that goes over the stain, and the sealer is the piece a stain-and-seal job stands or falls on.

What a patio coating does instead

An exterior coating or overlay is a wear layer. Textured acrylic overlays, polyaspartic with grit, and thin cementitious resurfacers under a sealed finish are different products doing the same job. They cover the concrete rather than tinting it, so spall repairs and mismatched patches disappear and the surface gets a texture you can feel with a wet foot. There is now material between the weather and the slab.

The trade is that a coating has to bond, and a bonded film over concrete that moves, sweats, or freezes is a film that can fail. Exterior coatings around here are specified for that. Plain garage epoxy is not, which is why it doesn’t go outside.

The three things a Cape Girardeau patio has to survive

Every exterior job here gets sorted by the same three exposures. Walk your own slab through them.

July sun

Sun does two things to a patio. It fades color and it heats the slab. Acid stain is mineral and holds up well in UV. Water-based color fades faster, and the sealer over any stain is where sun damage usually shows first: a clear coat going chalky, or yellowing if somebody used the wrong chemistry. You can see the fade on older stained patios in the rectangle where the grill mat or the doormat sat all summer. The shaded concrete still has its color. The rest went pale.

Coatings fade too if the top layer isn’t UV-stable, which is the reason exterior work uses aliphatic materials and not plain epoxy. Heat is where they pull ahead. A dark stained slab in full sun is a dark slab. A light, textured overlay reflects more of that heat and is noticeably cooler under a bare foot, which matters far more on a pool deck than on a patio you cross in shoes.

Freeze-thaw and road salt

Missouri winters push water into concrete and freeze it there, and then the deicer tracked off the driveway onto the steps finishes the job. None of this touches a stain. It can’t crack because it isn’t a layer, and the slab freezes and thaws the same way it always did. The sealer over it needs to breathe, though. A dense film-forming sealer over a slab that sits on damp ground goes cloudy white from underneath, the same moisture whitening that happens to basement floors.

A coating has to be built for movement. Rigid films crack when the slab moves, so exterior systems here are specified flexible, with crack repair done in flexible polyurea before anything goes over the top. Done that way, the coating is also the better defense against salt, because it puts a sacrificial layer between the deicer and the concrete instead of leaving the slab surface to scale on its own. Salt-spalled steps are almost always bare or stained concrete. Coated ones show the salt on the coating instead.

Pool water and wet feet

This is the exposure that decides most pool deck jobs on its own. A stained deck is as slick as the concrete under it, and pool decks are troweled smooth. Sealer on top makes it slicker. You can add grit to a sealer, and for a patio that’s a fine answer, but a pool deck wants texture built into the wear surface, not sprinkled on. Add chlorinated and salt-water splash on the same square feet every day and the sealer over a stain is the fastest-wearing spot on the whole slab.

For pool decks, then, it’s a coating, and specifically the cool-touch textured kind. Stain-and-seal belongs on the patio and the covered porch.

When the slab needs concrete resurfacing before either

Sometimes the question isn’t stain or coating, because the surface you’d be staining or coating is already gone. Scaling from salt, spalls where the top skin has popped, pitting deep enough to hold water. A stain will color all of that and highlight it. A coating can go over a patched slab, but patches under a thin overlay telegraph.

That’s the resurfacing job. The slab gets ground, the spalls and cracks repaired, and a new cementitious or polymer wear surface goes over the whole thing, bonded to the old concrete. It costs a fraction of tear-out, and it only makes sense on a slab that’s structurally sound. A patio that’s heaving, sinking at one corner, or pitched back toward the house has a drainage or base problem, and no surface product should be used to hide it. We’ll say replace when it’s replace. Once it’s resurfaced, the new surface can take texture and color, so you end up with the coating look anyway.

Which one for your patio

A quick sort, using the three exposures above:

• Sound slab, mostly shade or a covered porch, you like the concrete look: stain and a breathable sealer.
• Sound slab in full sun, walked in shoes, cracked or patched: a UV-stable textured coating.
• Pool deck, any condition: a cool-touch textured overlay, nothing else.
• Scaling, spalling, or pitted anywhere: resurface first, then choose.

Both approaches start with the same prep. Grind or profile, repair, then the system. That’s true on every exterior job we do, and it’s where the two paths cost about the same. They part at the wear layer. Exterior overlays and pool deck systems run $6-10 per square foot installed in the Cape Girardeau area, and a stain-and-seal on a slab that needs no repair comes in under that. The full local ranges by system are on the cost page, and the number that matters for your patio gets pinned in writing after the slab is seen.

If you’re deciding this week, do one thing before you call anyone. Pour a glass of water on the worst-looking spot and watch it. If it soaks in and darkens the concrete, the slab is open and breathing, which is good news for both stain and coating. If it beads up, there’s an old sealer or cure compound on the surface, and whatever goes on next has to start with getting that off.