Paver Sealing: Do You Actually Need It, and What Does It Cost?

Let me answer the question you came here with, before the pitch.

Pavers do not need to be sealed. Not structurally, not to keep them functioning, not to stop them falling apart. A paver surface is held together by three things: a compacted base, an edge restraint, and sand in the joints. Sealer is not one of them. Unsealed installations in this region go twenty and thirty years without a coating and do their job the entire time.

Every page ranking for this term is selling you sealer, so that sentence is worth repeating: if you are looking for permission to skip it, and your surface is in good condition, you have it.

What sealing buys you is real — color, stain resistance, joint stability, easier cleaning. It is just not survival. Once you see that difference, the decision gets simpler.

Do pavers need to be sealed?

No. Here is what a sealer does and does not do.

It does not add structural strength. A paver that cracks was going to crack. A surface that settles, settled because the base was wrong. Sealer does not fix a base problem, and any contractor implying it will is selling you the wrong service — what you need there is paver repair, not a coating.

It does not stop weeds forever. It slows them. Weeds come from seed landing in degraded joint sand, so fixing the sand is what fixes weeds. Sealer helps hold that sand in place — a real benefit, but downstream of the sand.

It does not make the surface permanent. Sealer wears. Every sealed surface is on a re-seal clock.

What it does do:

• Color. This is the honest number-one reason people seal. A sealer — particularly a film-forming one — deepens the color and can give a wet look. Unsealed pavers in this climate go grey and chalky-looking over time. If the way your patio looks matters to you, this is the strongest argument in the whole article.
• Stain resistance. Pavers are porous. Oil dripping on a driveway, grease under a grill, red wine on a patio — an unsealed paver drinks it. A sealed one gives you time to wipe it up.
• Joint sand stability. A sealer helps lock polymeric sand into the joints so it does not wash out in a heavy Pacific Northwest winter. Fewer washed-out joints means fewer weeds and less shifting.
• Easier cleaning. Moss and algae still grow on a sealed surface. They just do not bite in as hard, and they come off with less fight.

When sealing is genuinely worth the money

Sealing earns its cost in specific situations, not as a blanket rule:

• Driveways. Oil and transmission fluid are the whole argument. This is where stain resistance pays for itself.
• Outdoor kitchens, grill areas, dining patios. Grease, sauce, wine, food traffic. Same logic.
• A new install you want to hold its color. Sealing preserves the reason you paid for that paver.
• A surface whose joints keep washing out. If you are re-sanding constantly, a sealer plus fresh polymeric sand can end that cycle.
• Pool decks and light-colored stone, where staining shows badly.

Where it usually is not worth it: a low-traffic back walkway, a utility path down the side of the house, a surface nobody looks at or spills on.

When sealing is a bad idea

This is the section the sealer vendors leave out.

Sealing too soon after installation. New concrete pavers release efflorescence — a white, powdery mineral haze — as they cure and shed moisture. Seal over it and you can lock a permanent white cloud under the coating. Let the efflorescence run its course first. There is no rush; unsealed pavers are not deteriorating while you wait.

Sealing a dirty or damp surface. Whatever is on the paver when the sealer goes down is now under the sealer: moss, dirt, a stain, trapped moisture. Water trapped beneath a film-forming sealer can produce a milky blush that is a genuine pain to reverse. In Western Washington, getting a surface truly dry is harder than people expect, and it is the single most common reason a sealing job goes wrong here.

The wrong sealer, or too much of it. Over-application, poor technique, or a product mismatched to the paver material produces a blotchy, hazy or streaky finish. Stripping a bad sealer is far more work than applying a good one.

Slipperiness. A gloss film-forming sealer creates a smooth surface. Add the algae film that coats nearly everything outdoors here for half the year and you get a surface that is genuinely slick. On shaded, sloped, or damp walkways, this is a real safety consideration — and a reason we will often talk a customer out of the gloss finish they came in asking for.

The commitment. Once you seal, you have signed up for a cycle — typically a re-seal every 3 to 5 years. A sealed surface that is allowed to lapse looks worse than one that was never sealed, because the coating breaks down unevenly. If you will not keep it up, do not start.

How to clean pavers

Cleaning is not the optional prelude to sealing. It is the job. A sealer applied over a dirty surface is a worse outcome than no sealer, and a good cleaning alone often solves the problem that sent the homeowner looking for sealer in the first place.

Moss and algae — the Pacific Northwest problem

Around here, this is the issue. Roughly 38 inches of rain a year, months of surfaces that never fully dry, and shade from fir and cedar — moss and algae are not an occasional nuisance in South Puget Sound, they are the default state of any horizontal surface you do not maintain.

The sequence that works: kill it with an appropriate moss or algae treatment, wait for it to die, then remove it. Blasting live moss off with a pressure washer relocates the spores and chews up your joint sand at the same time. Pressure washing is a step, not the whole plan — and it needs the right pressure and tip, or you erode the paver face and blow the sand out of every joint.

Efflorescence

The white chalky bloom on new pavers. It is mineral salts migrating out of the concrete — normal, and not damage. It often weathers off on its own over a season or two, and an efflorescence cleaner will remove it. What you must not do is seal over it.

Organic and oil staining

Leaf tannins, berries, moss stains, barbecue grease, and motor oil each want a different approach — degreaser for oil, an oxygenated or enzymatic cleaner for organics. Test any cleaner in an inconspicuous corner first. Some acid-based products will etch or discolor certain stones.

Weeds in the joints

Weeds are a symptom of failed joint sand. Pull or kill them, then fix the actual problem: re-sand the joints.

Joint sand: the step people skip

Polymeric sand is a jointing sand with a binder in it. Wetted and cured, it firms up into the joints, resists washout, and slows weed germination.

It does not last forever. Winter runoff, aggressive pressure washing, and normal wear pull it out. If your joints are visibly low, hollow, or sprouting, the sand needs replacing — and it needs replacing before any sealer goes down, not after.

On a real clean-and-seal job the sequence is: clean, dry, re-sand where needed, let the sand cure, then seal. Any quote that skips the sand inspection is quoting a cheaper job than the one you need.

What paver sealing costs

Ranges below are typical of the industry, not ND quotes — we price every job itemized after seeing the surface, and I would rather you know the shape of the number than have me invent a precise one.

Three things move that number more than anything else:

1. Surface condition. A neglected, moss-covered patio is a cleaning job with a sealing job attached. A well-kept one is mostly just the sealer.
2. Joint sand. Whether it needs replacing, and how much.
3. Sealer type. Which is worth its own section.

And the cost nobody quotes: the re-seal. Every 3 to 5 years, most of that number again. Multiply before you commit.

Penetrating vs film-forming sealer

There is no best sealer, and I am not going to name a brand I have no business endorsing. There are two families, and they trade off against each other.

Penetrating (impregnating) sealers soak into the paver and protect from within. They barely change the appearance — no gloss, no color pop. They do not peel, they do not blush, and they do not make a surface slippery. They are the low-drama, low-risk option, and for a shaded Western Washington walkway they are usually the right call.

Film-forming sealers leave a layer on top. This is what gives you the wet look, the deepened color, and the strongest surface stain barrier — and it is what most people are actually picturing when they picture "sealed pavers." The cost: they can peel, blush, haze if applied wrong or over moisture, they get slick when algae settles on them, and they need re-coating more attentively.

Cutting across both: water-based products are lower-odor and lower-VOC; solvent-based ones typically penetrate harder and produce a stronger wet look. The right pick depends on your paver material — concrete, clay and natural stone do not behave the same — your sun and shade, and how much you care about that wet look.

How we handle it

Three things about how ND does this that are worth knowing before you call anyone:

We will tell you if you do not need it. If your surface is in good shape, low-traffic, and not staining, the honest recommendation is a cleaning and fresh joint sand — and we will say that instead of selling you a coating and a maintenance cycle. I would rather lose a sealing job and be the person you call for the patio.

The estimate is itemized line by line. Cleaning, moss treatment, joint sand, sealer, coats — each on its own line, so you can see exactly what you are paying for and what happens to the number if you drop something. The number you sign is the number you pay.

One hundred percent in-house crew, no subs. Sealing is an application-technique job. Coverage rate, dry surface, even passes — a sloppy applicator produces a blotchy patio that costs more to strip than it did to coat. The crew applying your sealer is our crew.

What to do next

If your pavers are sound and you are not fighting stains, you can stop reading — clean them, re-sand the joints when they get low, and get on with your life.

If you want the color back, you are tired of oil marks on the driveway, or your joints keep washing out, sealing is a legitimate answer. See how we scope it on our paver sealing service page, or get an itemized estimate — we will walk the surface with you and tell you straight whether it is worth doing.