If you’ve just had your concrete driveway water blasted and cleaned, you’ve probably been asked: “Do you want it sealed too?” It’s a fair question — and a lot of homeowners aren’t sure whether it’s worth it, what it actually involves, or whether it’s just an upsell. Here’s a straight answer, based on what we see on driveways across New Zealand every week.
Why Concrete Driveways Need Help in the First Place
Concrete looks solid, but it’s actually porous. Under a microscope, it’s full of tiny channels and pores that soak up whatever sits on the surface — rain, oil drips, tannins from leaves, dirt, and grime. Over time, that’s what causes the grey blotching, black mould spots, and general dullness you see on driveways that haven’t been maintained.
New Zealand’s climate doesn’t do concrete any favours either. Frequent rain, humidity, and shaded, damp corners of a property are the perfect breeding ground for moss, lichen, and algae. Once those get a foothold in the surface of the concrete, they’re much harder to remove — and they come back faster next time. This is exactly why a water blast on its own, while it makes a huge visual difference, is really only step one. It cleans what’s already there. It doesn’t stop it coming back.
What Sealing Actually Does
A penetrating sealer soaks into the concrete rather than just sitting on top of it like a coating. Once applied, it helps protect the surface from moisture, staining, and the general wear that comes from cars, foot traffic, and our unpredictable weather. It also makes future cleaning easier, since dirt and grime have a harder time bonding to sealed concrete.
Think of it as closing up those microscopic pores we mentioned above. With the pores sealed, there’s simply less surface area for moss spores, algae, and stains to grab onto in the first place. That’s the real value of sealing — it’s not about making the driveway look different, it’s about making the clean result you already paid for last a lot longer.
It’s worth being clear about what sealing won’t do. It won’t make an old, cracked driveway look brand new, it won’t fix existing structural damage, and it’s not a substitute for cleaning — the surface needs to be properly prepped first. But on a driveway that’s already been properly cleaned, sealing is one of the best ways to protect that result and slow down how quickly it gets dirty again.
The Product We Use
We apply Peter Fell Ltd (PFL) penetrating sealer, in two coats. It’s a trusted New Zealand product built for exactly this kind of residential application, formulated to handle local conditions rather than being a generic import, and it’s backed by the manufacturer’s own warranty against product defects.
We stick with PFL because consistency matters with sealers — the same product, applied the same way, following the same guidelines, gives predictable results. That’s not something you get by chasing whatever’s cheapest at the time.
How the Job Works
Sealing isn’t a same-day, one-visit job — and it shouldn’t be. Rushing the process is one of the most common reasons a sealing job underperforms. We split it across two visits:
- First visit — preparation. We prep the surface with an acid wash. This step matters more than most people realise: it opens up the pores in the concrete so the sealer can actually penetrate, rather than just sitting on the surface where it will wear off quickly and unevenly. Skipping or rushing this step is the single biggest reason DIY sealing jobs fail early.
- Second visit — sealing. Once the surface is properly prepped and fully dry, we apply the two coats of sealcoat. This visit typically takes 4–5 hours, depending on the size of the driveway. Two coats give more even, durable coverage than a single heavy coat, which tends to pool in low spots and leave thin patches elsewhere.
We follow Peter Fell’s official application guidelines throughout — checking surface preparation, moisture levels, and coverage rates — to make sure the product performs the way it’s designed to. Applying a sealer onto a surface that’s still holding moisture, or in the wrong weather conditions, is a common mistake that leads to cloudy patches, poor adhesion, or a sealer that simply doesn’t bond properly.
Why Timing and Weather Matter
Sealer needs the right conditions to cure properly — generally a dry surface, no rain forecast for a reasonable window afterward, and moderate temperatures. Applying sealer right before a downpour, or on a still-damp surface after washing, is one of the fastest ways to waste the product and end up with a patchy, unsatisfactory finish. This is part of why we treat prep and application as two separate visits rather than squeezing everything into one day — it gives the surface time to dry properly and lets us pick the right conditions for the actual sealcoat application.
How Long Does It Last?
Under normal residential driveway use, you can expect the sealer to last 3–5 years before it needs reapplying. How long it lasts on your driveway specifically depends on a few factors:
- Traffic levels — a driveway with two cars and regular foot traffic will wear faster than one that’s rarely used.
- Weather exposure — driveways that cop full sun, heavy rain, or are near the coast tend to see the coating break down faster.
- Concrete movement — all concrete shifts slightly over time with temperature changes and ground movement, which can affect how evenly the sealer holds.
- Surface prep quality — a well-prepped surface holds sealer significantly longer than one that wasn’t properly acid-washed beforehand.
Signs Your Driveway Might Need Sealing (or Resealing)
If you’re not sure whether your driveway is due, a few signs are worth watching for:
- Water no longer beads on the surface and instead soaks straight in
- The concrete looks patchier or duller than it used to, especially after rain
- Moss or algae is starting to reappear noticeably faster than before
- Oil or tyre marks are staining rather than wiping off
- It’s been roughly 3–5 years since the last sealing
None of these are urgent problems on their own, but together they’re a good sign it’s time to get it looked at before staining sets back in properly.
DIY Sealing vs Getting It Done Professionally
It’s entirely possible to buy a sealer and apply it yourself over a weekend, and plenty of people do. Where it tends to go wrong is in the details: getting the surface prep right, picking a day with the right weather window, applying an even coat without pooling or missed patches, and using a product suited to the specific type and age of concrete. A sealer applied over a poorly prepped or still-damp surface often looks fine for a few weeks before patches, cloudiness, or early wear start showing — at which point the product has been wasted and the job needs redoing properly anyway.
The advantage of getting it done professionally is mostly about getting it right the first time: proper acid-wash prep, application that follows the manufacturer’s coverage and moisture guidelines, and a result that’s actually built to last the full 3–5 years rather than falling short of it.
A Word on Warranties
We want to be upfront about this: we don’t offer an ongoing service warranty on liquid coatings like sealers. That’s not us dodging responsibility — it’s because things like concrete movement, weather exposure, and general wear are outside anyone’s control once the product is down. No sealer, however well applied, can be guaranteed against those external factors indefinitely.
What we do guarantee is that the application itself is carried out with professional care and skill, strictly following the manufacturer’s official guidelines on surface preparation, moisture checking, and coverage rates. We carry out every job in accordance with best trade practices. And the product itself is separately backed by Peter Fell’s manufacturing warranty against defects.
Frequently Asked Questions
Can I seal my driveway without getting it cleaned first? Sealing over dirt, moss, or stains just traps them under the coating. Proper cleaning and prep always needs to happen first — that’s exactly why we treat surface prep as its own visit.
Does sealing change the look of my driveway? A penetrating sealer generally enhances the natural look of the concrete slightly without leaving a glossy or plastic-looking film. It shouldn’t dramatically change the colour or finish.
How soon can I drive or walk on it after sealing? Cure times vary depending on conditions, which is part of why timing and weather matter so much for a good result — your installer will be able to give you a clear timeframe on the day based on conditions.
Is sealing only for driveways? No — the same principle applies to other exterior concrete and paved areas exposed to similar wear, though driveways are where it tends to matter most given the traffic they get.
Is It Worth It?
If you’ve already invested in getting your driveway professionally cleaned, sealing is a natural next step to help protect that investment for the next few years rather than watching moss and staining creep back in within months. It’s not a magic fix for damaged concrete, but done properly — with the right prep, the right product, and the right conditions — it makes a real difference in how your driveway holds up and how easy it is to keep clean.
Have questions about whether sealing is right for your driveway? Get in touch and we’ll take a look.