Driveway Sealer: Which Drives Need Sealing and Which Don't
Whether you need a driveway sealer depends entirely on the surface. Pattern imprinted concrete needs it, and should be resealed every few years. Exposed aggregate benefits from it. A resin bound drive laid with UV-stable resin does not need sealing at all, and a tarmac drive is not sealed as routine maintenance, although a faded one can be refreshed. Using the wrong product on the wrong surface causes more problems than not sealing.
Driveway sealing by surface: the short version
Pattern imprinted concrete: yes. The sealer is part of the finish. Reseal every three to five years, sooner on heavily used areas.
Exposed aggregate: usually. A protective sealer every few years helps resist staining and keeps the stones looking fresh.
Resin bound: no. The resin already binds and protects every stone. There is nothing to reseal.
Tarmac: not as routine. A restorer coating can refresh faded tarmac, but it is cosmetic and will not fix cracks or sinking.
The rest of this post explains why, and what to watch for if you do seal. It is the same advice we give on site visits for new driveways in Wolverhampton, because aftercare is part of choosing a surface.
Imprinted concrete: sealing is not optional
On pattern imprinted concrete, the sealer is what holds the colour and keeps water, oil and frost out of the surface. When it wears off, the coloured surface layer is exposed to traffic and weather, and on busy areas it can wear down to show the plain concrete underneath.
Industry guidance puts resealing at every two to four years; on the drives we lay we recommend every three to five, depending on how much traffic the drive takes and how exposed it is. The signs it is due are easy to spot: the colour looks flat and dull when dry, water soaks in rather than beading, and wheel tracks look paler than the rest.
The sealer we use holds a non-slip additive, which matters on a sloping or shaded drive. That is worth checking with anyone resealing a decorative concrete drive: a plain gloss sealer without grip can be slippery when wet.
Exposed aggregate: a protective coat every few years
Exposed aggregate is concrete with the stones in its surface left showing. It is hard-wearing without a sealer, but a protective sealant applied every few years adds durability and helps prevent stains soaking in. Regular sweeping and an occasional wash do most of the work.
Resin bound: do not seal it
A resin bound drive is stone fully coated in resin. Every stone is already bound and protected, so it needs no sealer, and on the drives we lay there is no resealing, no re-sanding and no weeding. We use UV-stable resin, which is what stops the surface turning amber in sunlight.
There is also a reason not to coat it. A resin bound drive laid on a permeable base drains through the gaps between the stones. Anything that forms a film over the surface could block those gaps and stop it draining the way it was designed to. Look after it with a sweep, a hose down and prompt attention to spills and moss. Our resin bound driveways page covers the aftercare in more detail.
Tarmac: restore it, do not seal it
Tarmac (strictly, asphalt or bitmac) is held together by bitumen. Over years in sun and rain the surface fades from black to grey and loses some of its fine material. A tarmac restorer is a coating brushed or sprayed on to bring back the colour. It can make a tired drive look much better, but it is a cosmetic treatment.
Two cautions. First, solvents are the enemy of tarmac: petrol, diesel and some oils dissolve the bitumen binder, so a solvent-based product meant for another surface can soften and damage it. Only use something made for asphalt. Second, if the drive is cracked, rutted or sinking, the problem is in the base, and no coating will fix it. That needs a repair or a relay.
How to seal a driveway: the steps that matter
For surfaces that do need it, the method decides whether the sealer lasts or fails.
Clean thoroughly. Remove moss, algae, oil stains and dirt. Anything left under the sealer gets locked in.
Let it dry completely. This is the step most often rushed. A good rule of thumb is three consecutive dry days in summer and five in cooler months before sealing, because moisture inside the concrete wicks up and reacts with the sealer.
Check the forecast. Rain on an uncured sealer causes problems. Follow the product's drying times.
Use the right sealer for the surface. A sealer made for block paving or natural stone may not suit decorative concrete, and tarmac needs a product made for asphalt. Check the label says it is made for your surface.
Apply thin, even coats. Two thin coats are better than one thick one. Thick sealer is more prone to turning cloudy and slippery.
Keep traffic off it for as long as the product says.
Resealing imprinted concrete is a DIY job for a careful homeowner, but stripping and correcting a sealer that has gone wrong is not.
What goes wrong with driveway sealers
Milky or white patches. Usually moisture trapped under the sealer, because it went on too soon after rain or washing.
Slippery when wet. A brand new sealer can be very smooth, and water beads on it. In most cases this eases within a few months as the surface weathers; a sealer with an anti-slip additive avoids it.
Poor bonding. A sealer applied over dirt, moss or an old coating it does not suit will not grip the surface properly.
Patchy colour. Uneven coats, or sealing in direct hot sun so it dries before it levels out.
Wrong product. A sealer designed for another surface, or one diluted to go further.
If a drive has been sealed badly, it often needs stripping back before it can be resealed properly, which is far more work than doing it right first time.
Driveway sealer questions, answered
Will sealing stop weeds?
On imprinted concrete and resin, weeds rarely grow through the surface anyway, because there are no sand-filled joints. They usually appear at the edges, in the narrow movement joints cut into a concrete slab, or in debris sitting on top.
Can I pressure wash before sealing?
On imprinted concrete, yes, with care and with plenty of drying time afterwards. On resin, a low-pressure setting is safer. Never seal straight after washing.
Does sealing make a drive last longer?
On imprinted concrete and exposed aggregate, keeping the sealer in good condition protects the surface and helps it last. On tarmac and resin, the lifespan comes down to the base and the installation, not a coating.
How each surface weathers, and what it costs to look after, is part of choosing one in the first place: our comparison of driveway materials sets that out side by side. On the drives we lay across Wolverhampton and the West Midlands, we finish imprinted concrete with the sealer and can take care of resealing it in later years too.
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