What is kiln dried sand?

Kiln dried sand is a specially processed jointing material used in block paving installations. The sand is heated in a kiln to strip out moisture content, creating a product that remains dry and stable when applied between paving blocks. Once brushed into the gaps, it absorbs moisture from rain or groundwater, rehydrating slightly and hardening into a solid joint that locks the blocks together.

The primary purpose of kiln dried sand in paving is twofold. First, it prevents individual blocks from shifting or settling unevenly by filling the joints and distributing load across the surface. Second, by sealing the gaps, it stops weeds from germinating in the soil beneath and blocks the entry of standing water, which can lead to frost damage or subsidence over time.

Quality kiln dried sand is clean, free of organic matter, and graded to a specific particle size so it compacts effectively into narrow joints. It differs from ordinary building sand, which may contain clay, silt, or moisture that would prevent proper joint formation. For block paving in Cheltenham, using kiln dried sand is standard practice among professional installers because it delivers a durable surface that requires less maintenance and resists the damp conditions common to the area. Block paving contractors will typically supply and install it as part of their paving works.