Gaps open between pavers when the jointing sand that locks them together washes out or breaks down, or when the base underneath shifts and pulls the pavers apart. Once that sand is gone, pavers lose the friction that holds them tight against each other and start drifting, especially at edges and high-traffic spots.
Jointing sand does more work than it looks like it should. It fills the narrow gaps between pavers and locks them together through friction, which keeps the whole surface acting like one connected unit instead of a bunch of loose pieces. If the edge restraint around the perimeter is missing or has failed, pavers can also spread outward over time under traffic and frost movement, which opens gaps starting at the edges and working inward.
Up here, freeze-thaw runoff speeds up sand loss. Heavy rain or snowmelt running across the patio surface carries loose jointing sand out of the gaps, especially if regular sand was used instead of a product designed to resist washout, or if the patio's grading sends water across the joints instead of off the edge. Ants and other insect activity can hollow out joints from below as well, adding to the same problem from a different direction.
We install edge restraint properly on new patios so the whole system stays contained, and we recommend polymeric or other washout-resistant jointing sand where the site's slope and drainage call for it. On existing patios, we can clean out failed joints and refill them, which is often a straightforward fix if the base and pavers underneath are still sound.
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Chelo's Brick & Stone serves Hillsville, Galax, Wytheville, Fancy Gap, and Independence, VA. Call for a straight answer and a free on-site estimate.
