Polymeric Sand for Florida Pavers: When It Helps and When It Fails

Pull a weed out of a paver driveway in Jacksonville and you will usually find the reason it was there: the sand between the pavers is gone. Rain washed it out, ants carried it off, and the joint filled with dirt and seed instead. Polymeric sand is the standard answer. It works well — and it fails in a very particular way when the job is rushed, which in a Florida summer is easy to do.

What polymeric sand is

It is fine joint sand mixed with a binder. Swept dry into the joints and then misted with water, the binder activates and the sand cures into a firm, slightly flexible joint. A cured joint resists washout in a storm, makes it hard for weeds to root and for ants to tunnel, and keeps the pavers from creeping sideways.

When it helps

• Re-sanding after cleaning. Pressure cleaning blows out the old joint sand. Refilling with polymeric sand is what holds the joints for the next few years.
• Joints that keep washing out. On a driveway or pool deck where every storm takes sand with it, a cured joint stays put.
• Weeds and ants. A full, hard joint gives them much less to work with than loose sand.
• Before sealing. Sealer goes on after the sand has cured, and it helps lock the joint in. That is why a proper visit is clean, re-sand, then seal.

When it fails

Almost every failure we see traces back to water arriving at the wrong time or the sand going in the wrong way.

• Rain before it cures. Most manufacturers ask for roughly a day of dry weather after activation. Uncured sand that meets a downpour washes out of the joint or runs across the surface. From June through September, when Jacksonville gets about half its rain in afternoon storms, finding that dry window is the hardest part of the job.
• Swept onto damp pavers. If the pavers are still wet from cleaning, the binder activates on the surface instead of in the joint and leaves a hazy film that is hard to remove.
• Not enough sand, or not compacted. A joint filled only near the top forms a thin crust that cracks and lifts out. The joint has to be filled deep and settled before it is misted.
• Too much water when misting. Flooding the joints washes the binder out of the sand; too little leaves the bottom uncured.
• A base that moves. Polymeric sand cannot fix sunken or root-lifted pavers. If the base is settling, the joints crack along with it. Those sections are lifted and relaid first.
• Water that stands on the pavers. A low spot that holds a puddle after every storm will keep softening the joint. That is a drainage problem — a slope correction or a channel drain — not a sand problem.

Paver sealer vs polymeric sand

They do different jobs, and people often ask which one they need. Polymeric sand fills and locks the joints. Sealer protects the face of the paver: it brings back the color the sun faded, resists oil and stains, and keeps the surface easier to wash. On a driveway in Florida sun you usually want both, in that order, every two to three years.

How we do it in Jacksonville

1. We schedule by the forecast, not the calendar, and the drier months — March to May — are the easiest. In the rainy season we wait for a clear window rather than gamble on one.
2. Pressure clean, then let the pavers dry completely.
3. Sweep polymeric sand deep into the joints and settle it, then blow every grain off the paver faces.
4. Mist to activate, with the amount of water the product calls for.
5. Seal once the joints have cured. Usually you can drive on it 24 to 48 hours after sealing, depending on the product and the weather.

What it costs

We price cleaning, re-sanding with polymeric sand and sealing as one job: $1.25 to $3.50 per square foot in our area, driveways from $899. A 600 square foot driveway is about $900 to $2,000. See paver cleaning & sealing or rough out your own driveway with the paver cost calculator. Free inspection within 48 hours: (904) 561-1816.