Frequently Asked Questions

The question of why my house has screw piles is becoming an increasingly common question as more engineers are designing them into builds and more builders are realizing the benefits over a bored pier.

An engineer will design helical screw piles into a new build or renovation for several purposes:

  • The soil report indicates a P Classification; – P class soil is one that has a determined amount of soft soil that does not offer any structural integrity and the helical pile is designed to be screwed through the fill and support the dwelling on a more solid natural soil profile.
  • The soil report indicates H or E Classification; – H and E class soils are considered reactive type soils and with changing moisture conditions the soil can Heave or Swell creating problems through the house such as cracking floors, walls and ceilings. Soil reactivity is an increasing problem in Australia with changing weather conditions such a drought. A Helical pile is designed to be installed beyond the reactivity soil to minimise the effects of reactive soils and keep the house stable.

  • There are trees close to the build or trees that have been removed for the build; -Trees can create major structural issues with your build. A trees root system will change the surrounding soils behavior which can greatly affect the slab and therefore the house above it. Helical piles are used to be installed at a depth that the tree roots will not affect the house.
  • There is a sewer or stormwater close to the house; – A sewer or stormwater asset must be protected and measures out in place to protect it and the house should they need to be dug up and repaired in future.