Cable damage during installation and backfill is a persistent risk when bedding contains sharp, angular particles or oversized fragments. Our Thermal Cable Bedding Sand is processed to a fine, rounded grain profile that sits evenly around cables without creating pressure points or risking damage to sheathing and insulation — across XLPE-insulated medium and high-voltage power cables, PVC distribution cables, fibre optic lines, and combined power and data installations. For XLPE cables rated at 90°C, insulation integrity is directly tied to current-carrying capacity and long-term reliability.

No sharp particles / No pressure points on sheathing / XLPE 90°C compatible

Cables generate heat under load, and the bedding must conduct that heat away efficiently to prevent conductor temperature from exceeding the insulation rating. Our sand provides low, consistent thermal resistivity — the key parameter in cable ampacity calculations. A well-graded, clean sand with high quartz content and good compaction characteristics achieves favourable thermal resistivity values, targeting below 1.0 K·m/W at design compaction and moisture. Thermal resistivity testing using the transient line-source method can produce the thermal dry-out curve used by engineers to model worst-case conditions.

Target below 1.0 K·m/W / High quartz content / Thermal needle probe testable

Standing water around buried cables accelerates corrosion, degrades insulation, and creates conditions for thermal instability. Our bedding sand is processed to remove clay, silt, organic matter, and fine contaminants that inhibit free drainage. Clay removal is particularly significant — even small clay content can dramatically reduce permeability, cause moisture retention, and introduce variability into the thermal resistivity profile. A clean, permeable bedding layer allows groundwater to pass through rather than accumulate around the cable.

Clay and silt removed / High permeability maintained / Stable thermal environment

Poorly graded or contaminated bedding materials with unpredictable thermal properties can force engineers to derate cables or increase burial depth — adding unnecessary cost and complexity to an installation. Specifying a clean, consistently graded bedding with known thermal resistivity characteristics from the outset removes that risk. Our material supports ampacity calculations based on reliable input data rather than conservative assumptions applied to compensate for unknown material performance.

No forced cable derating / No unnecessary depth increase / Reliable ampacity input