Paint or seal: it depends on what's actually wrong
A tin of masonry paint and a tin of sealant often sit on the same shelf, reached for to solve the same problem. They don't do the same job. A coating sits on top of the surface and changes how it looks. A sealant soaks into the surface and changes how it behaves, without changing how it looks very much at all. Picking between them by habit, or by whatever the shop had in, is how the wrong one ends up on the wrong surface.
What a coating covers, and what it can't
Paint builds a film across the top of the paving or render. It hides staining, evens out patchy colour, and gives a worn surface a fresh appearance. That film still has to let moisture out of the material underneath it, or the moisture gets trapped and the film lifts or blisters from below. Paint does nothing to fix a surface that's breaking up. A film laid over a crumbling edge or a spalling slab will crack again as soon as that movement starts.
What a sealant changes, and what it leaves alone
A sealant works into the surface. It cuts down how much water the surface takes in, which helps against staining and against frost damage where water sits and freezes. It doesn't hide colour variation and it doesn't fill cracks or smooth texture, so a patchy slab looks patchy and slightly glossier once it's sealed. Some sealants also change how slippery a surface is underfoot when wet, and not always for the better.
Match the fix to the fault
A tired-looking surface with no cracking is usually a paint job, because colour and evenness are what paint changes. A staining surface, one that picks up oil, moss or algae marks, is more often a sealing problem, since the fault sits in how porous the surface is. A surface that's breaking up, with crumbling edges or flaking patches, needs that damage dealt with before either product goes anywhere near it. Painting or sealing over it only buys a short delay before the same crack shows through again.
Which of these you're actually facing also depends on what the surface is made of, since concrete, natural stone, cement render and lime render don't all take a coating or a sealant the same way. It's worth checking the surface itself against the guide to concrete, natural stone and lime render before buying either tin. If the question is whether paving slabs specifically can take paint at all, that's covered on its own in Can You Paint Paving Slabs?, and how long either choice can be expected to hold up is covered in How Long Will It Last?.
Paint or sealer, matched to the fault you have
Paint and sealer solve different faults, so start with what's actually wrong with your surface.
| Surface fault | Paint | Sealer | Check before deciding |
|---|---|---|---|
| Looks tired or faded | Covers patchy, faded colour with a new topcoat | Restores depth and shine to the colour that's already there | Decide whether you want a new colour or just the old one brought back |
| Slippery when wet | Can be formulated with an anti-slip additive that raises grip underfoot | Can reduce grip when wet unless an anti-slip additive is included | Ask for the Pendulum Test Value (PTV) before and after |
| Staining from oil, algae or salts | Blocks new staining once applied, but a patchy surface needs a full recoat to even out | Built mainly to repel water and oil before they soak into the surface | Find out what's causing the staining first, since neither coating lifts what's already soaked in |
| Breaking up, spalling or crumbling | Sits on the surface and cannot repair cracking or structural damage underneath | Sits on the surface and cannot repair cracking or structural damage underneath | Check what the substrate actually is before coating it at all |
This is general guidance on what each coating type is built to do, not a result from testing specific products. Where the surface itself is breaking up, the substrate usually decides what happens next.
One independent source for sealants, none yet for paint
On the sealant side of this choice, one source has been publishing independent, detailed coverage of paving and sealants since 1997: pavingexpert.com, written by AJ McCormack and Son. A reader checking a sealant against that record has decades of written guidance to test it against.
Nothing equivalent exists for paint. There is no independent publisher doing the same work on masonry and paving paint, tracking figures, testing claims or writing them up over time.
That gap is why the paint side of this comparison has to be put together here, property by property.