Bored pier
Bored pier: a drilled in-situ concrete deep foundation for reactive and poor-soil residential sites. Extends to competent bearing strata below problem layers.
Ask Chalkline about this →A bored pier is a deep concrete foundation formed by augering a cylindrical hole to a competent bearing stratum, lowering a steel reinforcing cage, and pouring concrete in place. Common diameters for residential work range from 300 mm to 600 mm, with depths typically 2 m to 8 m depending on site class and soil profile. Bored piers are used where near-surface soils are reactive, soft, or on uncontrolled fill that cannot carry residential loads. Design and installation must comply with AS 2870:2011 Appendix G and AS 2159:2009.
Also known as: bored pile, drilled pier, cast-in-place pile.
Category: Foundations.
Related
- Pier footings, the full process article covering bored piers, driven piles, and screw piles for residential builds
- Site classification, the AS 2870 soil class system that triggers pier footing use
- Reactive soil, the soil condition driving most pier footing use in Australia
See also
- Footing, the general term for residential foundation elements
- Screw pile, the alternative steel helical pile for reactive and tight-access sites
Last updated: 2026-05-10. Verified: 2026-05-10. Quarterly review for currency.