How to Clean Pavers Before Sealing: The Data Sheet Sequence

If you want a sealer to bond, last and look even, you have to clean pavers before sealing. Sealer locks in whatever is on the surface, so oil spots, rust marks and white efflorescence left behind stay visible under the finish for as long as the sealer does.

The short version: spot treat stains first, fix or replace any contaminated joint sand, then wash the whole surface with an efflorescence or preseal cleaner, rinse until no foam remains and let everything dry for the time your sealer's data sheet calls for. For the Alliance Gator sealers, that is at least 48 hours with no rain.

Below is how to clean pavers before sealing the way the manufacturers publish it, with figures taken from their technical data sheets (TDS). Always follow the instructions on your pail or bottle and the current data sheet for your product.

Why you need to clean pavers before sealing

Techniseal's product guide explains that new pavers should be cleaned in their entirety so whitish efflorescence is not trapped under the sealer's film, and that sealing dirty older pavers will not give the intended result and can shorten the sealer's life.

Alliance Gator's Efflorescence Cleaner data sheet calls efflorescence cleaning "a necessary step before a sealer is applied," so the sealer can penetrate the freshly opened pores. SRW Products' catalog says the same thing in its own way: whether or not you need a spot cleaner, SRW recommends its PW Paver Wash or DW Dual Wash before sealing any project.

The cleaning sequence manufacturers specify

The Gator Hybrid Seal, Gator Seal Wet Look and Gator Seal Signature Series Natural Look NF data sheets list the same preparation order. Techniseal frames it as clean, prepare, apply.

1. Test the cleaner and the sealer on a small hidden area of about 4 sq. ft.
2. Remove all stains with the right spot cleaner. Use Gator Sealer Stripper to remove any unknown coating still on the surface.
3. Remove contaminated joint material and refill with polymeric sand, following the bag instructions.
4. Wait for the sand to harden: at least 48 hours with no rain, at the minimum temperature on your sealer's data sheet.
5. Clean the entire surface with Gator Efflorescence Cleaner.
6. Wait again at least 48 hours with no rain so the sand and paver surface are dry.
7. Seal with one coat, as each of these data sheets specifies.

Step 1: Spot treat oil, grease, rust and old sealer

Oil and grease

Gator XP Oil and Grease Remover is a poultice. Per its data sheet: shake the bottle, apply a 1/8 in coat that extends 1 in past the edge of the stain, let it dry completely to a powder (12 to 24 hours depending on temperature, humidity and ventilation), then sweep it up and repeat if needed. Use it on dry surfaces above 40°F; it is not recommended for synthetic oil and may damage an existing seal. Techniseal Pro-Grade Oil and Grease Remover and SEK Surebond Oil Extractor are other options in our paver and stone cleaners collection.

Rust

With Gator Rust Remover, the data sheet says to apply it to the stain, let it soak 2 to 3 minutes, scrub with a hard bristle brush, rinse and repeat until the stain dissolves. Afterward, clean the entire surface with Gator Efflorescence Cleaner so the color is uniform. Do not let it dry on the surface.

Old or unknown sealer

New sealer needs bare pavers. Gator Sealer Stripper is applied at least 1/8 in thick in manageable 10 ft by 10 ft areas, covered with plastic and left to react for at least 12 hours, then pressure washed and rinsed. Its data sheet lists an average spread rate of about 40 to 50 sq. ft. per gallon, and it performs above 50°F and below 90°F.

Step 2: Fix the joints first (sand before sealing)

According to the Gator sealer data sheets, joint sand goes in before the final wash and before sealing, never after. The joints must also harden first, and each sand manufacturer sets its own wait before cleaning or sealing. These are separate figures for separate products, so use the one for the sand in your joints.

Joint sand	Wait before cleaning or sealing (per data sheet)
Gator polymeric sand under Gator sealers	At least 48 hours with no rain before the efflorescence wash. The Efflorescence Cleaner sheet adds "above 59°F."
Techniseal HP NextGel	Joints must be hard first; typically at least 7 days and up to 30 days
Techniseal SmartSand	Joints must be hard first; typically 30 days
Techniseal NOCO	At least 7 days, and the joint must be hard
SRW X-Treme and SRW SimplyTough	28 days before cleaning or sealing
SEK PolySweep	No sealing wait stated; curing can take up to 24 hours or longer. Check with SEK.

Need new sand? Our polymeric sand collection lists joint width ranges for each product.

Step 3: The full surface wash

A general cleaner lifts dirt, while an efflorescence cleaner removes white mineral deposits and opens the surface for the sealer. The Gator Shampoo data sheet states that it "is not an efflorescence cleaner."

Cleaner	Job	Mix (per data sheet)	Coverage (per data sheet)
Gator Shampoo	Ground in dirt, routine cleaning	4 parts water to 1 part product	1 gal of concentrate plus 4 gal water cleans about 375 sq. ft.
Gator Efflorescence Cleaner	Efflorescence, preseal cleaning	4 parts water to 1 part product	About 40 sq. ft. per diluted gallon (about 200 sq. ft. per gallon of concentrate)
Gator Efflorescence and Slurry Remover	Efflorescence and slurry	8 parts water to 1 part product	About 40 sq. ft. per diluted gallon (5 gal plus 40 gal water cleans about 1,800 sq. ft.)

For Gator Efflorescence Cleaner, the method is: wet the pavers, apply the diluted product with a pump sprayer or watering can, wait one minute, scrub hard with a stiff bristle brush, rinse, and move to the next 40 sq. ft. section. Once the surface is clean, rinse with a hose until there is no more foaming action. Both Gator data sheets warn that a stronger mix than listed can discolor pavers, and that you should not let the product dry on the surface.

For routine dirt before the efflorescence step, Gator Shampoo is applied the same way on wet pavers in 75 sq. ft. sections, keeping the surface wet from start to finish. Other preseal cleaners we carry include Techniseal Paver Prep and HD Paver Prep Efflorescence Cleaner, which Techniseal lists as preparing pavers before sealant application, SEK Surebond SureClean and Efflo Off, which SEK lists as preparing unsealed surfaces for sealing, and SRW PW Paver Wash. Not sure which suits your pavers? Order a few from our 8 oz paver cleaner samples and test them side by side.

Rinse and dry times before sealing

Rinsing is complete when no foam remains. Drying is where the sealer data sheets differ, so go by the one for the sealer you bought:

• Gator Hybrid Seal (High Gloss and Low Gloss): wait at least 48 hours at a minimum of 60°F with no rain so the sand and paver surface are dry. Apply between 40°F and 85°F, and not if rain is expected within 24 hours.
• Gator Seal Wet Look (solvent based): pavers and joint sand must be 100% dry, with 48 hours of dry conditions before sealing. Apply between 60°F and 85°F.
• Gator Seal Signature Series Natural Look NF: wait at least 48 hours at a minimum of 41°F with no rain. It must go on a dry surface, between 41°F and 85°F.

All three also require the paver surface to be cool to the touch. When you clean pavers before sealing with another brand's system, use that brand's data sheet from our TDS and SDS library.

Common mistakes that ruin a seal

• Sealing over efflorescence after just a general wash.
• Mixing cleaner stronger than the data sheet ratio.
• Letting cleaner dry on the pavers, or working in hot, strong sun.
• Adding joint sand after the final wash, or sealing before the sand has cured.
• Skipping the 4 sq. ft. test area, or sealing a damp surface when the data sheet calls for a dry one.

Frequently asked questions

How long after cleaning pavers can you seal them?

It depends on the sealer. The Gator Hybrid Seal, Wet Look and Natural Look NF data sheets each call for at least 48 hours with no rain after the efflorescence wash, at the minimum temperature listed on that sheet. Check your sealer's data sheet.

Does polymeric sand go in before or after sealing?

Before. The Gator sealer data sheets list sand replacement ahead of the final efflorescence wash and sealing. Wait for the sand to harden for the time on the sand's own data sheet.

Can a general paver cleaner replace an efflorescence cleaner?

A general cleaner such as Gator Shampoo removes dirt but is not an efflorescence cleaner, per its data sheet. The Gator sealer sheets specify the Efflorescence Cleaner for the final preseal wash.

Do you need to pressure wash before sealing?

The Gator cleaner data sheets use a hose, pump sprayer and stiff brush. SRW's catalog cautions that pressure washing can drive dirt deeper into the pores. A pressure washer is part of the Gator Sealer Stripper method.

Will paver cleaners hurt polymeric sand joints?

The Gator Shampoo data sheet says it will not negatively affect polymeric sand joints. For freshly installed Gator sand, the Efflorescence Cleaner sheet says to wait 48 hours above 59°F with no rain before using it.