Soil, ground and cracking in Castle Hill
Castle Hill sits on the ridges of the Hills District, where Wianamatta Group shale weathers to clay over Hawkesbury sandstone. Clay soils move as they wet and dry, which is one reason brick veneer and render crack, especially near windows and where articulation joints were never provided. AS 2870 site classes are set lot by lot from a soil test, so we do not quote a single class for the suburb. Keeping water away from the footings is the part an owner controls.
Wianamatta shale weathers to clay over Hawkesbury sandstone.
Reactive clays shrink and swell with moisture.
Site class under AS 2870 comes from a soil test for your lot.
Ground falling toward the house keeps the clay wet.
Cracks at window corners often trace back to missing articulation joints.
More about Castle Hill
- Buying a home in Castle Hill NSW
- Building a new home in Castle Hill NSW
- Growth and development in Castle Hill
- Certifiers, council and building disputes in Castle Hill
- Termite and timber pest risk in Castle Hill
- Common building defects found in Castle Hill homes
- Wind, bushfire and site conditions in Castle Hill
Written by our local inspection team from work carried out in Castle Hill. Licensed building practitioners, NSW Fair Trading licence 366177C.


