Void Detection and Subsurface Scanning

About this service

GPR surveys to detect voids, washouts and poor compaction beneath concrete slabs, tarmac and paved surfaces. Early detection prevents costly structural failure and safety incidents — particularly important for highways, car parks, warehouses and industrial floors.

How GPR Detects Voids Beneath Slabs

Ground-penetrating radar transmits a pulse of electromagnetic energy into the ground and records the reflections from subsurface features. A void — whether caused by water erosion, poor compaction or ground movement — produces a strong, characteristic reflection that is clearly distinguishable from solid material. We scan in a grid pattern across the survey area to build a complete picture of subsurface conditions, identifying the location, approximate depth and lateral extent of any voids present.

When to Commission a Void Detection Survey

Void detection surveys are most commonly commissioned when floor slabs show signs of movement, cracking or deflection; before major plant or racking installations on industrial floors; as part of pre-purchase due diligence on commercial or industrial property; following nearby excavation or groundworks; and on highways or car park decks where surface defects suggest underlying loss of support.