How to Clean, Sand, and Seal Pavers — The Complete Process

By Jason Geiman, King of Pressure Wash | 136,000+ views on YouTube

Paver cleaning, sanding, and sealing is one of the most profitable add-on services you can offer as a pressure washing contractor. A driveway or patio made of pavers looks incredible when it’s been properly cleaned and sealed — and homeowners are willing to pay a premium for the transformation. But the process has multiple steps, and skipping or rushing any of them will show in the final result.

I’ve been cleaning and sealing pavers professionally for over 15 years, and I’ve refined this process through hundreds of jobs. In this post, I’ll walk you through the complete process from start to finish — cleaning, sanding, and sealing — so you can deliver professional results and add a high-margin service to your business.

Step 1: Clean the Pavers

The first step is getting the pavers thoroughly clean. You can’t sand or seal over dirt, algae, and old staining — the sealer won’t bond properly and the final result will look terrible.

Pre-treat with chemical

Apply a cleaning solution to the paver surface before you start pressure washing. For organic growth like algae, mold, and mildew, a sodium hypochlorite (bleach) solution with a surfactant works great. For oil stains and heavy grime, you may need a dedicated degreaser. Let the chemical dwell for 5-10 minutes to break down the contamination.

Pressure wash the surface

Use a surface cleaner to clean the paver surface evenly. Move slowly and overlap your passes to avoid leaving stripes. The chemical pre-treatment does most of the heavy lifting, so the surface cleaner is mainly removing the loosened grime and giving the pavers a uniform clean.

Pay special attention to the joints between pavers. The old sand in those joints is going to come out during the cleaning process — and that’s okay. You’re going to replace it with fresh polymeric sand in the next step. Don’t worry about trying to preserve the existing joint sand.

Let the pavers dry completely

After cleaning, the pavers need to dry completely before you move on to sanding and sealing. Depending on the weather, this can take anywhere from 24-48 hours. The pavers should be bone dry — not just surface dry. Moisture trapped in the pores will prevent the sealer from bonding and can cause the sealer to turn white or cloudy.

Step 2: Sand the Joints

Once the pavers are clean and dry, you need to fill the joints with polymeric sand. This sand is specially formulated to harden when activated with water, locking the pavers in place and preventing weed growth and insect intrusion in the joints.

Spread the polymeric sand

Pour the polymeric sand onto the paver surface and use a push broom to sweep it into the joints. Work the sand back and forth across the surface, making sure it fills the joints completely. The joints should be filled to within about 1/8 inch of the top of the paver — not flush with the top, and not so low that there’s a visible gap.

Remove excess sand from the surface

This is a critical step that a lot of people rush. Before you activate the sand with water, you need to get every grain of excess sand off the paver surface. Any sand left on top of the pavers will harden when you mist it with water, and then it’s stuck there. Use a leaf blower to blow the excess sand off the surface while making sure the joints stay full.

Activate the sand with water

Lightly mist the entire surface with water using a garden hose with a shower nozzle. You want a gentle mist — not a heavy stream that blasts the sand out of the joints. The water activates the polymers in the sand, causing it to harden and bind together. Follow the manufacturer’s instructions for how much water to apply and how long to let it cure.

Step 3: Seal the Pavers

Sealing is the final step, and it’s what transforms the pavers from clean to stunning. A good sealer enhances the color of the pavers, gives them a wet look or matte finish (depending on the product), and protects them from UV damage, oil stains, and future organic growth.

Choose the right sealer

There are two main types of paver sealers: water-based and solvent-based. Water-based sealers are easier to apply, have lower odor, and clean up with water. Solvent-based sealers typically provide a deeper color enhancement and a more dramatic wet look. Both work well — choose based on the look the homeowner wants and the product you’re comfortable applying.

Apply the sealer

Apply the sealer using a pump sprayer or roller, depending on the product instructions. Work in manageable sections and maintain a wet edge to avoid lap marks. Two thin coats are better than one thick coat — a thick coat can pool in low spots and create an uneven, sticky finish. Let the first coat dry according to the manufacturer’s instructions before applying the second coat.

Let it cure

After sealing, the pavers need time to cure. Keep foot traffic and vehicles off the surface for the time specified by the sealer manufacturer — typically 24-48 hours. Make sure the homeowner knows not to walk on or drive on the pavers during this period.

Common Mistakes to Avoid

Sealing wet pavers. This is the number one mistake. If the pavers aren’t completely dry, the sealer won’t bond properly and can turn white, cloudy, or peel. Always make sure the pavers have had adequate drying time.

Leaving excess polymeric sand on the surface. Any sand left on the paver face will harden and leave a rough, gritty texture that’s very difficult to remove. Take the time to blow off every grain before activating with water.

Applying sealer too thick. More sealer is not better. A thick coat pools, creates an uneven finish, and takes much longer to dry. Two thin, even coats give a better result than one heavy coat.

Not pre-treating before pressure washing. Pressure washing alone won’t remove deeply embedded stains and organic growth. Chemical pre-treatment is essential for getting the pavers truly clean before sanding and sealing.

Sealing in direct sunlight on a hot day. Heat causes the sealer to flash-dry before it can level out properly, leading to an uneven finish. Try to seal in the early morning, late afternoon, or on an overcast day when temperatures are moderate.

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