Every re-sanding job comes down to a choice of what actually goes into the joint, and the two realistic options — kiln-dried sand and polymeric sand — aren't simply cheap-versus-premium versions of the same product. They behave differently once installed, and that difference matters more on some drives than others.
Getting this choice right isn't about picking the newer or more expensive-sounding option by default; it's about matching the sand to the way the specific driveway drains, slopes and gets used.
Kiln-dried sand: the standard for a reason
- Loose, dry sand brushed into the joints and settled with vibration or repeated brushing.
- Simple to top up in future without removing what's already there.
- Allows the joint to drain and breathe normally, which suits most standard block paving.
- Can wash out gradually on slopes or under heavy repeated pressure washing over time.
Polymeric sand: designed to lock in place
- Contains a binder that activates when the sand is wetted after installation, hardening it in the joint.
- Resists washout and weed penetration more effectively once fully cured.
- Needs precise installation — any residue left on the block faces can haze or bond to the surface if not cleaned off before it sets.
- Must be fully removed before re-application, since it doesn't top up the way loose sand does.
Where the extra durability of polymeric sand earns its cost
A sloped drive that keeps washing sand out at the bottom, or a drive where weeds return within months no matter how often it's swept, is the situation polymeric sand exists for. The binder resists exactly the two failure modes — washout and weed germination — that make some drives high-maintenance under kiln-dried sand.
Drives near heavy tree cover with constant organic debris landing in the joints are another case where the added resistance to weed growth pays off over time.
Where kiln-dried sand remains the sensible default
For a flat, well-draining drive with no particular washout or weed history, kiln-dried sand does the job at lower cost and is simple to maintain — a light top-up now and then rather than a full removal and reinstallation. Most driveways fall into this category, which is why it remains the standard choice.