Comparison Chart for Screw Piles

Item Helicastâ„¢ Screw Piles Alternative Piling Methods
Soil suitability
Suitable for all soil types
No Spoil
Suitable for contaminated sites & asbestos sites
Suitable for acid sulphate soils
Building on weak soils or difficult conditions
Excellent for Tension & Compression
Can penetrate rock
Suitable for selective soil types

Acid sulphate oxidisation issues when exposed
Contaminated Soil
Weather suitability
Install can be done in inclement weather
May not used in certain weather conditions
Concrete requirement
No concrete required

No curing time so loads can be applied immediately
Concrete & reinforcing steel required for bored piers.
Curing time required for concrete to achieve desired strength, up to 4 weeks.
Soil disturbance
No spoil generated
Spoil generated with bored piers & exposure oxidisation to acid sulphate soils
Installation disturbance
Vibration free and minimal noise
Larger installation impacts with vibration/drilling of driven piles or bored piers
Installation speed
Efficient and accurate installation. The multi turn helix is quick to install.

Available for immediate use
Longer installation time and curing time
Cost saving
Reduce time and cost on site
Larger cost on site & cost of disposing of spoil or contaminated soil
Bearing capacity
Greater resistance to uplift due to Bulb effect of multi turn screw helix gives pile an improved load capacity.
Standard bearing capacity only utilised.
Space limitation
Ideal for working within close proximity of trees, roots and sites with limited spaces. Short interlocking piles for internal building rectification, repairs and underpinning.
Low Head Height
May not suitable for limited spaces. Joining of extensions slow and costly.
Foundation depth
Multiple extensions suitable for deep piling
Quickly extended on site, no welding required.
Only available to designed depth.
Availability in water
No de-watering
Suitable for high water table
Limited in high water table conditions. Bored piers unusable with high water table due to collapsing soil and water ingress.
Other
Greater shaft capacity can be used due to less concern for helix flex. The multifin helix is a cast product welded to bottom of shaft.