Polymeric sand is joint sand mixed with binders that harden when wet, locking pavers together and resisting weeds and washout. You should re-sand when joints look low, weeds appear or pavers start to shift. Exact timing varies with weather, traffic and how the patio was installed.

What is the difference between regular and polymeric sand?

•Regular joint sand pros: inexpensive, easy to install and easy to top off. Cons: washes out with heavy rain, lets weeds and ants in and needs refilling more often.

•Polymeric sand pros: hardens to a firm but slightly flexible joint, resists washout and weeds, and holds up better in heavy rain. Cons: costs more, is easy to install wrong and can haze the surface. It can also be hard to remove or repair.

Neither is perfect. Which is better depends on the site, the paver and how much upkeep you want to do.

Why does joint sand matter?

Joint sand holds pavers tight together so they interlock and share loads. Without it, pavers shift, edges chip and weeds take root. It also helps keep water and debris out of the base. In Summerville and across the Lowcountry, heavy summer rain can wash out joints, so sand condition matters.

What are the signs you need to re-sand?

•Joints look low or empty.

•Weeds or moss are growing between pavers.

•Pavers wobble or shift underfoot.

•Sand washes out after storms.

•Ants are nesting in the joints.

•You have just done a deep cleaning.

How do you re-sand pavers?

•Clean the surface and remove weeds and old loose sand.

•Let the pavers dry fully.

•Sweep the sand into the joints, filling them to the proper level.

•Compact the pavers lightly to settle the sand, and sweep again.

•Sweep or blow all excess sand off the surface. Leftover sand on top causes haze.

•Mist with water as the product directs, without flooding or washing it out.

•Let it cure, and keep traffic and rain off during that time.

 

Always follow the manufacturer's directions, since products differ.

 

What are the common mistakes?

•Haze: polymer residue left on the surface hardens into a cloudy film.

•Wet pavers or joints: sand can activate early and clump.

•Not activating properly: too little water means it does not harden, and too much washes the polymer out.

•Rain too soon: a storm during curing can ruin the joints.

•Joints not full or not compacted: leads to low spots and failure.

Who should do it?

Re-sanding is part of patio maintenance, a separate service from installation. Some owners do it themselves and some hire it out. Weather windows in the Lowcountry can be short, since humid, rainy conditions make timing harder. Check HOA rules on sealers and products.

Frequently asked questions

•How often should I re-sand?

It varies. Check the joints each season and re-sand when they look low.

•Can I put polymeric sand over old sand?

Usually the joints need to be cleaned out first, and the product directions vary.

•Does sand stop weeds?

It helps. Polymeric sand resists weeds better, but nothing stops them entirely.

•Planning a patio?

If you are in Summerville or the surrounding Lowcountry, we are happy to take a look. Every project starts with a free design and build estimate: an on-site visit, three price points for the same scope of work, and a custom 3D design once the project is booked. Every paver install includes a 10-year workmanship warranty. No pressure.