Ground Sun installed screw piles in the garden of this high end property in Hampstead. The screw piles were to secure a boundary structure and decking in the garden of this property. There was a requirement to protect the tree roots of the many established and protected trees in the area.
The foundations had to be at least 5 meters deep to get below the clay soils which were susceptible to moisture movement. To ensure no roots were damaged during the piling installation, small holes were excavated by hand to a depth of 750mm to ensure no roots were present. If roots are found, the hole is extended to the side to ensure there is an area of 200mm diameter (150mm is the largest helix) free of roots. No piling mats or tracked machinery are required and thus the feeder roots, generally located in the top 1m of soil, are not damaged from compaction.