Factors affecting selection of pile type

The choice of pile type depends on the following factors.

1. Soil and ground conditions: type and depth of firm strata, soft or loose layers, boulders, groundwater and aggressiveness of soil or water (corrosion, sulphates).
2. Magnitude and type of load: vertical, lateral or uplift; heavy loads need large concrete or steel piles.
3. Length of pile required: timber for short lengths, steel for very long piles, precast concrete for medium.
4. Installation method and equipment available, noise and vibration limits, and overhead clearance.
5. Effect on adjacent structures: displacement piles may heave soil and damage nearby buildings.
6. Durability: exposure to marine, sulphate or varying water levels (timber rots above water table).
7. Availability of material and local skill, transport and handling (precast piles are heavy).
8. Cost and time: total cost including driving, cap and testing.
9. Group action and settlement requirements, and the need for load testing.