Excavation & Earthworks

1. Ground Failure

• Trench collapse during excavation
• Slope or embankment failure
• Soil erosion after heavy rainfall

2. Damage to Adjacent Structures

• Loss of soil support to neighbouring foundations
• Undermining of walls, slabs, or boundary structures
• Cracking from settlement or vibration

3. Utility Strikes

• Damage to underground water, gas, or electrical services
• Broken drainage and telecoms cables
• Service outages and safety incidents

4. Ground Risks Encountered

• Weak or loose soil with poor bearing capacity
• High groundwater levels and waterlogging
• Expansive clay (swelling and shrinkage)
• Contaminated soil requiring specialist handling

5. Common Causes

• Poor planning or missing soil investigation
• Over-excavation beyond design depth
• Inadequate temporary support systems
• Heavy rainfall or uncontrolled water on site

minor Repairs

• Backfill and re-compact over-dug areas
• Reinstate small sections of damaged service
• Localised drainage improvements to control water

moderate Repairs

• Soil stabilisation using lime, cement, or geotextiles
• Install retaining walls or additional supports
• Repair damaged pipes, cables, and ducts
• Re-grade slopes to a stable angle

major Repairs

• Underpinning nearby structures affected by movement
• Strengthen or rebuild damaged foundations
• Sheet piling or secant walls to retain failing ground
• Comprehensive dewatering and drainage scheme

When Replacement Is Needed

• Before any new build, extension, or major groundworks
• When forming basements, drainage runs, or service trenches
• When ground levels need cut-and-fill to reach formation

Installation Steps

1. 1

   Site Preparation & Setting Out

   • Confirm levels, boundaries, and service locations
   • Mark out excavations from approved drawings
   • Agree spoil management and access routes
2. 2

   Excavation for Foundations

   • Dig to design depth and width
   • Inspect formation against soil report
   • Remove unsuitable material if encountered
3. 3

   Compaction & Grading

   • Compact granular fill in controlled layers
   • Grade to falls for drainage and slabs
   • Test compaction where specified
4. 4

   Drainage Installation

   • Install land drains, soakaways, and surface water runs
   • Bed and surround pipes with suitable material
   • Connect to existing or new outfalls
5. 5

   Temporary Support Systems

   • Shoring for trenches over 1.2m or in unstable ground
   • Sheet piling for deep or waterlogged excavations
   • Retaining walls for permanent support
   • Benching or battering sides where space allows