This low-maintenance polymer/sand blend forms a hard joint that won't let plants or ants get through, but it softens when wet, allowing water to drain. It's ideal for walkways or patios made with concrete, brick, or natural stone pavers, as long as the joints are ½
to 1 inch wide and at least 1½
inches deep. After 10 to 15 years, joints should be power-washed and refilled.
Stabilizing Sand. This green product uses plant fibers or tree sap to firm up sand or stone dust. Should it ever crack, it rebonds to itself after it gets damp. Organic sand is easier to remove than polymeric sand, which helps when replacing damaged pavers. Life span varies, depending on movement and amount of moisture, but it should be maintenance-free for two to three years. At that point, you just add more of the same material.
Sand-joint stabilizers. These acrylic- or epoxy-based liquids improve the elasticity and water resistance of existing sand- or stone-dust joints, as long as they're less than ½ inch wide. Also seals porous materials, like brick, but it will darken and create a sheen on any surface it touches. Sand-joint stabilizers last 5 to 7 years.