How to Clean, Re-Sand & Seal a Paver Patio (The Right Way)

Yes, a hardscape company is about to teach you to clean your own patio. Most maintenance is a homeowner job, and we'd rather you do it right than pay someone to do it wrong. Where you genuinely want a pro, we'll say so and why — the same straight talk as everything else on this site.

The golden rule: gentlest first

Paver cleaning goes wrong in one direction — too aggressive. Etched surfaces, blown-out joints, bleached-blotchy color: all of it comes from starting strong. So work up this ladder and stop at the first rung that works:

1. Water and a stiff nylon brush. You'd be surprised.
2. Dish soap in warm water. A few squirts, small sections, stiff brush, rinse. This is the workhorse for general grime — and it's what the paver manufacturers themselves recommend first.
3. A peroxide-based outdoor cleaner. For a whole-patio spring or fall refresh, something like Simple Green Oxy Solve Concrete & Driveway Cleaner is the sweet spot: peroxide-based, pH-neutral, EPA Safer Choice–recognized, and safe around plants and pets when used as directed. Mix about 1:20 for hand scrubbing, or run it through a pressure washer's soap setting — let it sit 3–5 minutes, don't let it dry on the surface, then rinse.
4. Stain-specific treatments — only on the spots that survive steps 1–3. Next section.

Never on your list: muriatic acid (it can permanently etch concrete pavers and shift their color), wire brushes (they shed steel fragments that rust into orange speckles), and never, ever mix bleach with vinegar or ammonia.

Stains, one at a time

Pressure washing without wrecking it

A pressure washer is a fine patio tool and a great patio destroyer, depending entirely on the hands. The rules:

• About 1,500 PSI is plenty for pavers — leave the 3,000 PSI contractor settings alone
• Fan tip, never the zero-degree pencil jet — held at an angle, 12–24 inches off the surface
• Keep it moving at a steady rhythm — hovering makes wand marks you'll see forever; a surface-washer attachment gives the most even result
• Test a hidden corner first. Every time.
• Expect to lose joint sand. A real wash blows sand out of the joints — that's normal, and it means re-sanding is part of the job, not an optional extra.

Re-sanding: the step everyone skips

Full joints aren't cosmetic — the sand is what locks thousands of pavers into one surface, and empty joints are an open invitation to weeds, ants, and shifting. After a wash (or every few years regardless):

1. Let the patio dry completely — polymeric sand and damp joints don't mix
2. Sweep polymeric sand diagonally across the joints until they're full
3. Tap or compact so the sand settles, top up, then sweep and blow the surface spotless — sand left on top hazes when wetted
4. Mist per the bag's directions to activate, and keep traffic off until it sets

As a reference from our own work, joint re-sanding runs about $0.50–$1.00 per square foot done professionally, every few years.

Sealing: when, how, and whether at all

First, the honest part: sealing is optional. A properly built paver patio doesn't need sealer to survive New England — ours don't fail unsealed. What sealer buys you is stain protection and looks: spills wipe up instead of soaking in, and color reads richer. Worth it next to the grill and on light-colored pavers; skippable on a patio you'd rather leave natural.

If you seal, the conditions matter more than the brand:

• New patio? Wait 60–90 days. Concrete pavers need time for efflorescence to dissipate — seal too early and you trap that white haze underneath, permanently.
• Weather window: 50–90°F (around 75° is ideal), with 24–48 dry hours before and after. In Greater Boston that means late spring or early fall, not July blacktop heat.
• Spotless and bone-dry first. Sealer locks in whatever's under it — clean, then wait a full day.
• Pick your finish: water-based sealers give a natural matte look with easy cleanup; solvent-based give the "wet look" and more sheen. Penetrating sealers protect invisibly with no sheen at all. Film-forming, joint-stabilizing products also firm up the sand — nice bonus.
• Apply with a pump sprayer or roller, thin and even, the whole patio in one session so the sheen matches — then keep feet off it (and irrigation off) for 24–48 hours.
• Reseal every 3–5 years, when water stops beading and the sheen goes flat.

Professionally, cleaning runs about $0.15–$0.40 per square foot and sealing about $1–$2 — the same numbers in our patio cost guide.

The seasonal rhythm (New England edition)

• Spring: the big wash — winter grit off, joints inspected, re-sand where the plows and thaw took it. Check for any settled spots while you're down there.
• Summer: spot-treat spills when they happen, not in October.
• Fall: get the leaves off before they sit wet — tannin stains are fall's souvenir. Last call for sealing while temps hold above 50°.
• Winter: plastic shovel or rubber-edged blade, and go easy on the salt — plain rock salt is rough on concrete surfaces. Never a metal blade on the pattern you paid for.

When to call us instead

DIY the soap and the leaves. Call when: a section has settled or heaved (that's a base problem wearing a dirt costume — see patio repair); joints empty themselves every season (drainage question); white haze won't quit after a year (moisture question); or the patio's big enough that cleaning, re-sanding and sealing it is your whole weekend and you'd rather it be ours. And if what winter broke is brick or stone, that's our masonry repair department.

37 years. 500+ patios across Greater Boston. Unilock Authorized Contractor. Licensed and insured.